The Church of San Pedro el Viejo is one of Madrid's oldest surviving churches. Its 14th-century Mudéjar tower rises over the narrow streets of La Latina as a quiet record of the city's layered past. Mudéjar, derived from the Arabic for "tamed animal," describes work produced by Muslim artisans under Christian rule: skilled craftsmen who were, formally, second-class citizens.

Local legend holds that the church's bell was too large for the staircase. Workers went for lunch and returned to find it miraculously installed. It reportedly rang three times of its own accord: at Felipe II's death, during the Alcázar fire, and on 2 May 1808, when Madrilenians rose against Napoleon's forces and were brutally put down.

VoiceMap's self-guided audio tours use San Pedro el Viejo to trace Madrid's Islamic heritage through the old morería, connecting the tower's brickwork to the Muslim craftsmen who shaped this part of the medieval city.