Abbazia di San Galgano is a Cistercian abbey located in the province of Siena, Tuscany, Italy. It was founded in 1218 by the nobleman Galgano Guidotti, who became a hermit and was later canonized as a saint. The abbey is renowned for its Gothic-style architecture and the nearby chapel of Montesiepi, which houses the famous Sword in the Stone.

The abbey was constructed in a cruciform shape with three naves, and features beautiful ribbed vaults and pointed arches. It is said to have been designed to reflect the purity and simplicity of the Cistercian order. The interior is decorated with frescoes and sculptures, including the tomb of Saint Galgano, which was created by the Sienese sculptor Giovanni Pisano.

The nearby Chapel of Montesiepi is a small octagonal building that was built in the 13th century. It is famous for the sword in the stone, which is said to be the sword that Saint Galgano plunged into the rock as a symbol of his devotion to God. The sword is said to have been miraculously embedded in the rock and has become a popular destination for pilgrims and tourists.

Today, the Abbazia di San Galgano is a popular tourist destination, and visitors can tour the abbey and the Chapel of Montesiepi, as well as attend concerts and other cultural events held at the site. The abbey has also been featured in several films and TV shows, including the James Bond film "Quantum of Solace."