| Pitzer Run | |
| Subdivision Type1: | Country |
| Subdivision Name1: | United States |
| Subdivision Type2: | State |
| Subdivision Name2: | Pennsylvania |
| Subdivision Type3: | Region |
| Subdivision Name3: | Adams County |
| Subdivision Type5: | Township |
| Subdivision Name5: | Cumberland |
Pitzer Run is a Pennsylvania stream flowing southward between McPherson Ridge and Seminary and Warfield Ridges through the Gettysburg Battlefield to Willoughby Run at the site of Pitzer's School, which was Confederate General Longstreet's headquarters during the Battle of Gettysburg (the school burned in 1915).
This site was the location of an important clash between Berdan's Sharpshooters and Longstreet's corps as they were assembling prior to Pickett's charge. General Sickles described this in his oration after the battle, noting "Col. Berdan pushing through the curtain of woods, hurled his dauntless little band directly against the force intended to crush in our left flank and seize the Round Tops."