To say that this was an amazing painting to see would be an understatement. It is 27 feet high and 359 feet in circumference. Here's a little more information on it:
The "Battle of Gettysburg" Cyclorama at Gettysburg National Military Park is one that has survived. This fantastic painting brings the fury of the final Confederate assault on July 3, 1863 to life, providing the viewer with a sense of what occurred at the battle long touted as the turning point of the Civil War.
The culmination of the battle was captured on canvas by the French artist Paul Philippoteaux, a professional cyclorama painter and artist. Philippoteaux was not present at Gettysburg, but came to the United States in 1879 when he was hired by a group of entrepreneurs to paint this monumental work for a special display in Chicago. Philippoteaux arrived in Gettysburg in 1882 armed with a sketchbook, pencils, pens, and a simple guide book to help him locate the site of the climactic charge. The artist spent several weeks on the battlefield, observing details of the terrain and making hundreds of sketches. To help him recall the landscape with accuracy, Philippoteaux hired a Gettysburg photographer to produce a series of panoramic photographs for his use. These images are some of the earliest detailed photographs of Cemetery Ridge, the Angle and the "High Water Mark", and the field of Pickett's Charge. Philippoteaux was also lucky enough to interview a number of veterans of the battle, who helped with suggestions on how to depict the chaos of battle.
There a narration of some of the important points shown in the painting. It is very impressive as you can tell by these pictures.