This UNESCO World Heritage cover features 2 stamps showing the 2 cathedrals in Coimbra. It is called the University of Coimbra - Alta e Sofia, the historic-cultural complex classified as a UNESCO World Heritage Site in 2013, housing 4 parishes in the Historic Center of Coimbra (São Bartolomeu, Sé Nova, Sé Velha and Santa Cruz) located in the city of Coimbra, in Portugal. The University of Coimbra is one of the oldest universities still in operation in the world and the oldest in Portugal and Portuguese-speaking countries and regions. Both cathedrals that we can see at this cover are part of this complex: Sé Velha (Old Cathedral) from the 12th century and Sé Nova (New Cathedral) from the 17th. century.
