Palencia Cathedral was built from 1172 to 1504 stands over a low vaulted Visigothic crypt (the Crypt of San Antolín). It is a large Gothic building, popularly dubbed as 'The unknown beauty' because not as well known as other Spanish cathedrals, though, it is a valuable building which has in its interior a large number of works of art of great value.
Its more than 130 metres long, 42 metres high and 50 metres wide at the centre, making it one of the largest cathedrals in Spain and Europe.
Its exterior solid, simple and austere does not reflect the grandeur of its interior, with more than twenty chapels of great artistic and historical interest. The most recognizable on the outside, is the tower, slim but a little rough, considering your Gothic style. Recent studies and excavations show that it was a military tower, and after serving this function were added to their pinnacles and cattail as the sole decoration.
The Cathedral's museum contains a number of important works of art, including a retablo of twelve panels by Juan de Flandes, court painter to Queen Isabella I of Castile and El Greco's St. Sebastian' (1576–79).
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.