The marker for the Powhatan Artillery is on the west side of Gettysburg on Seminary Avenue. (Seminary Avenue tour map) The battery was commanded at the Battle of Gettysburg by Lieutenant John Cunningham.
From the marker:
July 1. Reached the field in evening too late to take part in the battle.
July 2. Early in morning took position here. Opened fire about 4 P M. upon the batteries on Cemetery Hill and continued firing until dark.
July 3. Remained here all day. Took part in the great cannonade preceding Longstreet’s final assault. At night withdrew to camp in rear.
July 4. After nightfall began the march to Hagerstown.
Ammunition expended 308 rounds.
Losses not reported in detail.
See more on the history of the Powhattan Artillery in the Civil War.