Santa Maria della Spina is a small Gothic church in the Italian city of Pisa. The church, erected in 1230, was originally known as Santa Maria di Pontenovo: the new name of Spina ("thorn") derives from the presence of a thorn allegedly part of the crown dressed by Christ on the Cross, brought here in 1333. In 1871 the church was dismantled and rebuilt on a higher level due to dangerous inflitration of water from the Arno river: the church was slightly altered in the process, however.
The church is one of the most outstanding Gothic edifices of Europe: it has a rectangular plant, with an external facing wholly composed of marble, laid in polychrome bands. The exterior appearance is marked by cusps, tympani and tabernacles, together with a complicated sculpture decoration with tarsiae, rose-windows and numerous statues from the main Pisane artists of the 14th century.
Reference: http://en.wikipedia.org/wiki/Santa_Maria_della_Spina