First stop on the journey west is the town of YA'AN , which sits on the banks of the Qingyi River below Erlang Shan, five hours by bus from Chengdu or Emei across the flat Red Basin. Originally a garrisoned staging post on the trail to Tibet, and briefly the capital of Xikang before its dissolution in 1955, today Ya'an has ambition. The approach road tunnels through a hillside and on to an empty plain, where an isolated colonnade of tall street lights, the first stage of a massive urban expansion project, flank the highway into town. There's nothing to see here but buses always pull in for a meal and comfort stop - be warned that Ya'an bus station's toilets are possibly the worst in all China, however.