On the northern side of the plaza is the Casa Piar, where General Manuel Piar was kept prisoner in October 1817 before being positioned against the cathedral wall and executed by firing squad. Piar liberated the city from Spanish control, but rejected Bolívar’s authority and was sentenced to death in a controversial and much criticized trial. The plaque on the cathedral’s wall marks the spot where he was shot dead, while Bolívar watched the execution from the Casa del Congreso de Angostura.