Built in 1783 by Cpt. Robert Orr, this blockhouse stood in the town of Tarentum to protect traders when Tarentum was known as a resting area for hunters and traders. It had a trap door and no windows, only peep holes for firing rifles. Captain Robert Orr died in Kittanning on September 4, 1833. The original blockhouse may have been destroyed before March of 1791, and the blockhouse now in the park was built in 1976 and dedicated to the 200th anniversary.