Outside the city walls to the southwest is Long Tower Church , Derry’s first post-Reformation Catholic church. Built in 1784 in neo-Renaissance style, it stands on the site of the medieval Teampall Mór (Great Church), built in 1164, whose stones were used to help build the city walls in 1609. Long Tower was built with the support of the Anglican bishop of the time, Frederick Augustus Harvey, who presented the capitals for the four Corinthian columns framing the ornate high altar.