This 15th-century domed school is known as Alexander’s Prison because of a reference to this apparently dastardly place in a Hafez poem. Whether the deep well in the middle of its courtyard was in fact built by Alexander the Great and used as a dungeon seems doubtful, no matter what your guide tells you. The building itself is worth a look for the small display on the old city of Yazd, the clean toilets and the mercifully cool subterranean teahouse.
The early-11th-century brick Tomb of the 12 Imams is almost next door to Alexander’s Prison. The once-fine (but now badly deteriorated) inscriptions inside bear the names of the Shiite Imams, though none are actually buried here.