The Church was built after the death of St. Clare, between 1257 and 1265, around the ancient St. George's Church. The crypt that now houses the tomb of the Saint was only built in 1850. The architectural style is Gothic, and very reminiscent of the contemporary Upper Basilica of St. Francis of Assisi. The exterior is characterized by three large buttresses polygonal buttresses that reinforce the left side (XIV century). The facade is made of rows of local white and pink stone, tripartite frames. The portal has a round arch, with the ring around the bezel which is supported by two lions at rest. Higher up, the canopy has a double row of columns and arches. The bell tower, with a square base, it stands on the side, with large single lancet windows and surmounted by a spire. The interior has a Latin cross with a single nave, transept and polygonal apse. In the nave opens St. Agnes's Chapel: pentagonal, is dedicated to the sister of St. Clare and is decorated with frescoes of 1914 by Girolamo Marinelli and Sigismondo Spagnoli. On the right side opens the environment instead of the St. George's Chapel, already part of the original church, which leads to the Oratory of the Crucifix (or Relic), which preserves the original St. Damiano's Cross that, according tradition, spoke to St. Francis. The frescoes are by Francesco Tartaglia (1527). Also it accessed from the nave to the crypt. The Sanctuary is home to the altar by a series of twelve polygonal columns with Gothic capitals, the work of craftsmen in Umbria of the late twelfth century.