St. George's Basilica is the oldest surviving church building within Prague Castle and was founded by Vratislaus I of Bohemia in 920. It is dedicated to Saint George.

The basilica was substantially enlarged in 973 with the addition of the Benedictine St. George's Abbey. It was rebuilt following a major fire in 1142. The Baroque façade dates from the late 17th century. A Gothic style chapel dedicated to Ludmila of Bohemia holds the tomb of the saint. The shrines of Vratislav and Boleslaus II of Bohemia are also in the basilica. The abbess of this community had the right to crown the Bohemian queens consort.

The building now houses the 19th century Bohemian Art Collection of National Gallery in Prague.