Uzbekistan's sightseeing is a concentrated encounter with Timurid Islamic architecture at its peak. The Registan — three madrasas facing each other across a square covered in lapis and turquoise tilework — is one of the most architecturally perfect urban ensembles in the world, best visited at dawn before tour groups arrive. The conqueror's mausoleum holds a ribbed melon dome of lapis lazuli and gold. Bukhara's ancient minaret, the citadel, and the 16th-century trading domes extend the architectural sightseeing east. Khiva's walled city — virtually entirely preserved from the 18th-19th century — is the most physically intact historic city in Central Asia. Tours by locals add the missing layer. Take it all in.