Belváros (Inner City) Church is the oldest building in Pest side of river in Budapest. It was built in 1046 as a grave of Bishop St. Gellért (c. 980-1046), a missionary from Italy who played an instrumental role in converting Hungary to Christianity. According to tradition, he was martyred by angry pagans who rolled him down a hill across the river, which was named Gellért Hill in his honor.
The first church constructed on this spot was a 12th-century Romanesque structure built inside the ruined walls of the Roman fortress of Contra-Aquincum. In the early 14th century, after destroyed by Mongols, this church was replaced by a Gothic church which still stands today. It has been frequently renovated and remodeled in accordance with contemporary fashions, so its medieval origins are not obvious at first glance.
During the reign of Ottoman Empire Belváros was used as a mosque and in 1702 it was returned as a Christian church by Jesuits. The Rococo style pulpit dates from 1808.
The Basilica of Santa Maria in Trastevere is one of the oldest churches of Rome. The basic floor plan and wall structure of the church date back to the 340s, and much of the structure to 1140-43. The first sanctuary was built in 221 and 227 by Pope Callixtus I and later completed by Pope Julius I.
The inscription on the episcopal throne states that this is the first church in Rome dedicated to Mary, mother of Jesus, although some claim that privilege belongs to the Basilica di Santa Maria Maggiore. A Christian house-church was founded here about 220 by Pope Saint Callixtus I (217-222) on the site of the Taberna meritoria, a refuge for retired soldiers. The area was made available for Christian use by Emperor Alexander Severus when he settled a dispute between the Christians and tavern-keepers.
The church underwent two restorations in the fifth and eighth centuries and in 1140-43 it was re-erected on its old foundations under Pope Innocent II.