Trinitatis Church is part of the 17th century Trinitatis Complex, which includes the Rundetårn astronomical observatory tower and the Copenhagen University Library, in addition to the church. Built in the time of Christian IV, the church initially served the students of Copenhagen University.
The interior was seriously damaged in the fire of 1728 but was rebuilt in 1731. The bases and capitals of the columns and arches were repaired. All wood furnishings were replaced, and the floor was covered with tiles from Öland. The reconstruction was in Northern Gothic-Baroque style. The church was rededicated October 7, 1731 and the remains of the university library were moved again. The furnishings were renewed with an altarpiece and pulpit by Friederich Ehbisch (1731) and a large Baroque clock (1757). The church was refurbished in 1763.
References:The Chapel of St. Martin is the only completely preserved Romanesque building in Vyšehrad and one of the oldest in Prague. In was built around 1100 in the eastern part of the fortified outer ward. Between 1100 and 1300, the Rotrunda was surrounded by a cemetery. The building survived the Hussite Wars and was used as the municipal prison of the Town of the Vyšehrad Hill.
During the Thirty Years’ War, it was used as gunpowder storage, from 1700 to 1750, it was renovated and reconsecrated. In 1784, the chapel was closed passed to the military management which kept using it as a warehouseand a cannon-amunition manufacturing facility. In 1841, it was meant to be demolished to give way to the construction of a new road through Vyšehrad. Eventually, only the original western entrance was walled up and replaced with a new one in the sountren side. The dilapidating Rotunda subsequently served as a shelter for the poor.