Once a stopover on the Silk Route and a former Soviet Republic, Azerbaijan is known for its medieval castles, fire temples, palaces, and cultural charm. Baku is the biggest metropolis in Transcaucasia. Tourist attractions in Azerbaijan include the medieval walled city of Icheri Sheker, known for its tea-houses and the 12thcentury Maiden Tower; Apsheron Peninsula, famous for its 14th century castles at Ramana, Nardaran and Mardakan; Ateşgah Fire Temple, Khan's Palace, the 18th century Surakhany Fire Temple, and Gobustan Museum, an open-air museum known for its Neolithic rock inscriptions. The scenic Aspheron Peninsula also has some of the finest beaches in the country and offers good hiking and coastal walks.