Odds and Ends
Cannons, Cora, and Penelope (NEW)
Approximately 653 cannons were assigned to the two armies (372 to the Union Army and 281 to the Confederate Army) in the Gettysburg Campaign, and that today there are approximately 370 cannons that sit on the battlefield that had been placed by the Gettysburg Battlefield Memorial Association. This total does not include the 14 upright cannon tubes which mark the location of the headquarters of the major generals, nor does it take into account the many others requested and received from the War Department that were melted down into the bronze equestrian statues and other bronze markers.
It is important to know that due to a comprehensive, costly, and time-consuming restoration process begun in 2000 as a joint effort between the National Park Service and volunteers from the Friends of the National Parks at Gettysburg, about 150 cannons are still off the field. The good news is that all of the ones you now see have been restored, and no more have to be temporarily removed.
Only 1 cannon can be officially documented as having actually seen action at Gettysburg, and that is "Cannon Number 233" of Lieutenant John Calef's Battery A, 2nd U.S. Artillery, which fired the first Union artillery shot of the battle while under the command of General John Buford's cavalry division on McPherson's Ridge on July 1:

An interesting and lesser known fact about the cannons on the battlefield is that one of them was manufactured in 1866 and never fired a shot during the Civil War at all. I was not aware of this until I recently read the excellently written and highly informative book by George W. Newton entitled "Silent Sentinels: A Reference Guide to the Artillery at Gettysburg" (listed on my "Books Worth Reading" page). Located on East Cemetery Hill only a short distance south of the equestrian monument to Union General Winfield S. Hancock, look for the small monument to Cooper's Battery of the 1st Pennsylvania Artillery. Find the cannon with the number "931" at the top of the muzzle and "1866" on the middle-lower right side of the muzzle:

Two other interesting cannons are one named "Cora" (located along the north side of United States Avenue at the Abraham Trostle Farm near the small monument to Captain John Bigelow's 9th Massachusetts Light Artillery Battery of the Artillery Reserve):

and a dented cannon at Lieutenant Chandler Eakin's Battery H of the 1st U.S. Artillery located in the Soldiers' National Cemetery along the fence separating it from Evergreen Cemetery:

Generally speaking, there were three major types of cannons (or artillery pieces as they are called) -- the 12-pounder (bronze) Napoleon, the 3-inch (iron) Ordnance rifle, and the 10-pounder (iron) Parrott rifle. There were also a few of the 20-pounder Parrott rifles that are distinguished by the much larger breech (as seen in the bottom right photo):

(12-pounder Napoleon) (3-inch Ordnance)
(10-pounder Parrott) (20-pounder Parrott)
There were also other types of cannons used by the Confederate Army, including a 6-pounder bronze cannon (see the top two photos below) and a 12-pounder howitzer (see the bottom two photos below) at Captain A. C. Latham's Battery in General John B. Hood's Division on South Confederate Avenue:
(6-pounder bronze)

(12-pounder howitzer)
The Confederate Army also utilized foreign-made cannons, including 2 British Whitworth breech-loading cannons on Oak Hill at Captain W. B. Hurt's Battery of the Artillery Reserve:

and four Austrian 24-pounder howitzers with their unique "handles" on West Confederate Avenue at Captain George V. Moody's Battery of the Artillery Reserves:

What is perhaps not common knowledge is that there are 70 cannon "replicas" (36 10-pounder Parrott rifles, 18 3-inch Ordnance rifles, and 1 20-pounder Parrott rifle) on the battlefield which can be spotted if you look closely at them. There are also 15 so-called "false Napoleons" --- 6-pounder cannons that were modified to appear like the 12-pounder Napoleons.
Generally speaking, the replicas do not have the manufacturing information on the muzzle, the tubes are not always quite tapered the same, or other details are missing (like the initials "U.S." on the top of the tube of the Union cannons --- and remember, the Confederate Army also had captured Union cannons which they used). One example can be found in the Soldiers' National Cemetery near the memorial to the Gettysburg Address. One of the cannons at the monument to the 1st Massachusetts Light Artillery is a replica:

Of course, any section about cannons at Gettysburg would not be complete without mentioning
"Penelope", the ancient cannon fired after Democratic election victories until 1855 when its tube ruptured after such a celebration. Its final resting place is located outside the former office of the Compiler newspaper at 126 Baltimore Street:

To learn more about the cannons at Gettysburg, I highly recommend the book I mentioned earlier in this section, "Silent Sentinels: A Reference Guide to the Artillery at Gettysburg", by George W. Newton. You will be glad you did.
The other "citizen soldier" at Gettysburg (NEW)
I think it would be safe to say that everyone who ever visited the battlefield eventually learned about John Burns, the Gettysburg resident and War of 1812 veteran who, despite being over 70 years old, took up arms with the 150th Pennsylvania Infantry Regiment against the oncoming Confederate Army on July 1. However, I would venture a guess that very few people know that there was another "citizen soldier" at Gettysburg on that very day in 1863 as well. There is a also a monument honoring the Engineer Brigade (comprised of the 15th New York Volunteer Engineer Regiment and the 50th New York Volunteer Engineer Regiment) of the Army of the Potomac which was designed in the shape of the "castle" insignia of the Union Army Corps of Engineers: I have found two sources that delve into the actual weather conditions during the battle, the webpage found at http://gburginfo.brinkster.net/weather.htm , and the handy reference book "Gettysburg: By the Numbers" (see my "Books Worth Reading" page). To me, it was interesting to learn that according to those records, July 3, 1863, was the only day of the 3-day battle where the daylight temperature actually approached the 90-degree mark (87 degrees during the time of Pickett's Charge). Perhaps the most important factor to remember is that Daylight Saving Time did not yet exist. As a result, this should be taken into account when reading about the evening and/or early morning attacks on Culp's Hill and Cemetery Hill, and perhaps as a possible factor to consider as to one of the reasons why General Meade did not ultimately mount a counterattack after Pickett's Charge was repulsed.
A boyish-looking young man, whom soldiers in the 12th Massachusetts Infantry Regiment estimated to be no more than 16 years old, had encountered the regiment about 2 miles north of Emmitsburg on June 30, 1863 and expressed his desire to join in the fight. The young man was given a uniform and rifle, and was wounded twice the next day on Oak Ridge. Left behind during the regiment's eventual retreat to Cemetery Hill, his identity remained a mystery for many years due partly because of the fact that he was not officially mustered into service.
Years later in 1886, an article appeared in the Century Illustrated Monthly Magazine that provided a firsthand account of this nearly forgotten story and identified the brave young man as J. W. Weakley. Weakley was actually 21 years old at the time, survived his wounds, and later enlisted in the 13th Pennsylvania Cavalry Regiment. Sadly, this other "citizen soldier" at Gettysburg died in November of 1864 while suffering an epileptic seizure, and never received the acclaim that he deserved and was accorded John Burns.
To learn more about this forgotten hero, read the book "Human Interest Stories of the Gettysburg Campaign, Volume 2" or the book "Gettysburg: A Testing of Courage" (see my "Books Worth Reading" page).
Speaking of John Burns (NEW)
The statue of John Burns, located along the east side of Stone Avenue on McPherson's Ridge, is one of the many monuments and markers that have been moved in the past for one reason or another. In this case, Stone Avenue at one time ran on the other side of the Virginia worm fence behind the statue and then turned 90 degrees to the west and continued past the monument to the 7th Wisconsin Infantry Regiment. As a result, that monument now appears to be misaligned for the proper viewing of the front of it. Also, if you look on the other side of the fence behind the statue of John Burns, you can still see its former base nearby. So, when you see other monuments or markers as you drive on the battlefield that seem to be facing the wrong way, remember that is probably because the original park roads had been re-routed or removed entirely.

The two "castles" (NEW)
Every battlefield visitor to Little Round Top has no doubt observed the "castle" monument to the 12th New York and 44th New York Infantry Regiments: 

This unique monument, which is located along Pleasonton Avenue on Cemetery Ridge near the Pennsylvania Memorial, is probably overlooked by many people. That is truly a shame, especially since Major General Gouverneur K. Warren, Chief Engineer of the Union Army Corps of Engineers, is often referred to as "the Saviour of Little Round Top".
In any event, if you would like to learn more about the Union Army Corps of Engineers, go to the website at http://www.topogs.org/Engineers-1.htm .
The "Rule of 29" and the Pennsylvania Reserves (NEW)
If you look closely at the Union regimental monuments, you will see that some of them have dual military unit designations. Two such monuments are located at the summit of Big Round Top --- the monuments to the 5th Pennsylvania Reserves and to the 12th Pennsylvania Reserves:

The 5th Pennsylvania Reserves is also indicated as being the 34th Pennsylvania Infantry Regiment, while the 12th Pennsylvania Reserves is also indicated as being the 41st Pennsylvania Infantry Regiment, which leads us to what my friend and Licensed Battlefield Guide Mike Strong refers to as the "Rule of 29".
When President Lincoln called for troops after the attack on Fort Sumter in April of 1861, his quota of 14 regiments from Pennsylvania was quickly surpassed, and even though the quota was later increased because of the overwhelming number of volunteers, the remaining regiments were organized into the Pennsylvania Reserve Volunteer Corps consisting of 13 infantry, 1 cavalry, and 1 artillery regiment. All these regiments were not held in "reserve" very long --- 2 infantry regiments were mustered into the Union Army by late June, and all the remaining regiments were mustered in on July 22, 1861 after the First Battle of Bull Run to complement the 29 infantry regiments from Pennsylvania already in service and designated accordingly.
So, for example, when you hear or read about the 5th Pennsylvania Reserves and their actions on July 2, and the speaker or the author later refers to them as the 34th Pennsylvania Infantry Regiment in the same context, just remember the "Rule of 29". For more information on the history of the Pennsylvania Reserves, go to http://pareserves.com .
The first and the last monuments (NEW)
The first monument of any type was a marble urn placed in the Soldiers' National Cemetery in 1867 to honor the 1st Minnesota Infantry Regiment, which suffered 82% casualties during its heroic charge led by Colonel William Colvill on July 2 against an entire Confederate brigade under the command of General Cadmus Wilcox: 
The first monument placed on the battlefield (although the argument can obviously be made that the site of the cemetery was part of the battlefield) was to the 2nd Massachusetts Infantry Regiment in 1879 on Colgrove Avenue, which took part with the 27th Indiana Infantry Regiment in the ill-fated charge near Spangler's Spring on the morning of July 3 (see my "Off the Usual Path" page):

The last equestrian monument placed on the battlefield was in 1998 to honor Confederate General James Longstreet. Located in Pitzer's Woods just off West Confederate Avenue along Seminary Ridge, the monument is unusual for an equestrian one in that it is not set on a large pedestal: 
The last monument, honoring the 11th Mississippi Infantry Regiment, was placed on the battlefield in 2000 on Seminary Ridge along West Confederate Avenue near McMillan's Woods. A marker was also dedicated at that same time just a few yards south of the Abraham Brian barn on Cemetery Ridge to indicate the position that regiment reached during Pickett's Charge. I will be adding photographs in the near future.
In addition, there will be a monument dedicated on the North Cavalry Battlefield on July 2, 2008, at Hunterstown to honor the Union cavalry and General George Custer's participation in the action that took place there 145 years ago on that day. I will add photographs as soon as I can.
The 4th of July marker (NEW)
While it is not really a monument commemorating Independence Day, the small marker located along the west side of the Emmitsburg Road roughly 100 yards south of the Nicholas Codori barn indicates the location of the skirmish line of the 2nd Rhode Island Infantry Regiment on July 4, 1863:

It is the only marker that I am currently aware of that indicates a unit's position the day after the battle, but I am still checking into this. If anyone is aware of any others, please let me know and I will add them to this section.
Time and temperature
Geology of the battlefield
There is a 20-page booklet available from the PA Department of Conservation and Natural Resources which addresses the geology of Adams County and how it affected the battle. The booklet can be found at the webpage http://www.dcnr.state.pa.us/topogeo/education/es5/es5.pdf .
There is also a newer and much better report containing more than 100 pages and which includes tons of photographs and maps that definitely makes it worth taking a look at for that reason alone. The detailed report can be found at http://www.dcnr.state.pa.us/topogeo/pub/openfile/pdfs/of06_02.pdf .
In addition, there is an interesting website which I recently found that discusses this topic in the form of a field trip: http://www.howard.k12.md.us/white/GettysburgFT.html .
In any event, it is interesting to learn about this aspect of the battle and how the terrain and geology did more than make it difficult for the dead to be buried (more often than not) in shallow graves. I urge each student of the battle to take time to look into this seemingly boring aspect --- I think they will be glad they did.
"Witness trees"
While it is no doubt that there are many trees still standing that were "witnesses" to the battle (not counting, of course, some of the famous "copse of trees" on Cemetery Ridge) I have read of only seven or eight (I think, though, one of these was struck by lightning about 10 years ago and cut down) that have some documentation. These include three sycamore trees on Baltimore Street, a honey locust tree in the Soldiers' National Cemetery, a black walnut tree near the "copse of trees", and a white oak tree on the Abraham Trostle farm near the area of Union General Daniel E. Sickles' headquarters on July 2
and about 40 yards south of the monument marking the spot where he was hit by a cannon shell and lost part of his right leg:
I am researching these "witness trees" and will update this section in the future. If you are interested in this topic, go to http://www.bivouacbooks.com/bbv2i1s4.htm , which deals with the "witness trees" at not only Gettysburg, but also other Civil War sites. Also, if you would like to order a seedling from the honey locust tree in the Soldiers' National Cemetery, go to http://www.historictrees.org/civilwar.html .
The Springs Hotel
Two years ago, while "Googling" for battlefield maps of Gettysburg, I came across a 1904 map indicating the positions of monuments. What caught my attention, however, was that there was a "Springs Hotel" marked on the west bank of Willoughby Run in the area where General Archer's brigade crossed and then encountered the Iron Brigade on July 1. I had never heard of this hotel, and did some research as well as discussing it with Park Ranger Troy Harman after one of his enjoyable and enlightening "Battle Walks."
I mentioned to Troy that I had found the Springs Hotel marked on a map and then later read an article (http://www.emmitsburg.net/archive_list/articles/history/gb/property/springs_hotel.htm) I had found on the Emmitsburg Area Historical Society's website, and he mentioned that that was how Springs Avenue got its name --- a horse-drawn trolley line ran along present-day Springs Avenue and linked the railroad station downtown with the hotel. That small fact was of particular interest to me, since my great-great grandfather, who had been wounded in the fighting for the Wheatfield, returned after the war and built his own house on Springs Avenue, which, I am proud to say, still stands today.
But back to the story of the "Gettysburg Springs Hotel", or "Springs Hotel" as it was also referred to. Mineral springs were found on the farmland as early as the 1830's, and a health resort/spa was built in 1869 by the Gettysburg Katalysine Springs Company. The spa later closed in the 1890's, and the four-story hotel, which housed guests for the 50th anniversary of the battle in 1913, was eventually destroyed only a few years later by fire in 1917. For an excellent 1903 photograph of the Springs Hotel, visit the webpage at http://www.gettysburgcountryclub.com/history.html .
The last soldier found on the battlefield
Believe it or not, the remains of a soldier killed during the battle was found on March 19, 1996, wedged in the rocks on the southeast bank of the now-famous railroad cut, one of the many scenes of severe fighting on July 1. Prior to that time, remains were found in 1939 and 1914, and in both cases, were also attributed to the battle.
After a five-day archaeological excavation, as well as lengthier testing and research, the National Park Service concluded the human remains (found in the vicinity of the tiny orange arrow in the right photo) were most likely a Confederate soldier from the 2nd Mississippi Regiment, which had seen action there:
Following a proper military ceremony, this last ??? soldier found on the battlefield was buried later that year in the Soldiers' National Cemetery in the vicinity of the New York State Memorial.
Camp Colt
As surprising as it may be to believe that a trolley line and three amusement parks once existed on a portion of the battlefield, it is perhaps just as surprising to learn that Camp Colt, a World War I era training camp for tanks, actually existed on much of the very ground of Pickett's Charge. In fact, it is my understanding from a conversation with a park ranger that because of this, the terrain of a large part of this hallowed area was changed through grading and excavation, so what we see today is not exactly the same identical terrain those gallant men marched across on their way to the Emmitsburg Road. Another interesting fact is that a young Army captain by the name of Dwight D. Eisenhower was the commander of the camp. During World War II, a POW camp housing approximately 300 German prisoners was located on the former site of Camp Colt. Today, all that remains is a commemorative tree and marker along the Emmitsburg Road in the general location of the 192-acre camp:
Congressional Medal of Honor winners
It may be interesting to know that the Congressional Medal of Honor originated in 1862, and of the 1,520 awarded for action during the Civil War, 63 were awarded for action at the Battle of Gettysburg, including Colonel Joshua L. Chamberlain and also General Daniel E. Sickles (Sickles was awarded his medal about 34 years after the battle).
One of these 63 winners, Captain William E. Miller, of Company H, 3rd Pennsylvania Cavalry, is actually buried in the Soldiers' National Cemetery right along a main path near the New York State Memorial:
Captain Miller was awarded the Congressional Medal of Honor for helping to repel the Confederate cavalry charges under General J.E.B. Stuart's command roughly 3 miles east of Gettysburg on the afternoon of July 3.
(Photo courtesy of USAMHI)For more information on all of the 63 recipients and their citations for gallantry, visit the webpage at http://www.medalofhonor.com/GettysburgRecipients.htm .
Confederate Medal of Honor winners
Perhaps an even lesser known fact is that the South also has its version of the Medal of Honor which, due to financial issues and disagreements, was never awarded during the Civil War. However, the Sons of Confederate Veterans followed through with the idea and in 1977 posthumously awarded the first Confederate Medal of Honor. Since then, 52 medals have also been awarded, 5 of which were awarded for action during the Battle of Gettysburg:
Brigadier General Richard B. Garnett (Pickett's Division, I Corps) -- killed during Pickett's Charge on July 3
Brigadier General Wade Hampton (Stuart's Cavalry Division) -- for action on July 3
Colonel Henry K. Burgwyn, Jr. (26th North Carolina Infantry) -- killed on July 1
First Lieutenant William A. McQueen (Garden's Battery, Palmetto Light Artillery) -- for action on July 3 in support of Pickett's Division
Private Wilson J. Barbee (1st Texas Infantry) -- wounded several times during action on July 2 at Devil's Den
For a list of all 53 recipients, their units or ships, and fields of battle (land or sea), go to the webpage at http://www.medalofhonor.com/ConfederateHonorRoll.htm .