Gothic Piarist church in Krems was built in 1014. It was refurbished in mid-15th century. Its choir was consecrated in 1457 and later sanctified again in 1508 following the adaptations. Its frescoes and altar are credited to the famous artist M. J. Schmidt in Baroque architectural style. The church was also the theological college of the Piarists between 1636 and 1641.
References:The city walls of Avila were built in the 11th century to protect the citizens from the Moors. They have been well maintained throughout the centuries and are now a major tourist attraction as well as a UNESCO World Heritage Site. Visitors can walk around about half of the length of the walls.
The layout of the city is an even quadrilateral with a perimeter of 2,516 m. Its walls, which consist in part of stones already used in earlier constructions, have an average thickness of 3 m. Access to the city is afforded by nine gates of different periods; twin 20 m high towers, linked by a semi-circular arch, flank the oldest ones, Puerta de San Vicente and Puerta del Alcázar.