In short
Xi'an was the capital of thirteen dynasties and the starting point of the Silk Road. The Terracotta Army, found by farmers in 1974, numbers more than eight thousand figures, every one different.
The Ming city wall, fourteen kilometres around, is the most complete in China and is cycled along its top.
What it really costs
Xi'an costs markedly less than Beijing and Shanghai, for one of the densest heritage sites in the country.
The Muslim quarter and its night market feed you for a few yuan: Shaanxi cooking — biangbiang noodles, roujiamo — is one of the reasons to come.
What nobody tells you
The Terracotta Army is forty minutes from the centre. The site is visited in a specific order — pit 3, then 2, then 1 — so as to finish with the most impressive, and many people do the reverse.
The tomb of Emperor Qin himself is not open: it has never been excavated. What you visit are the satellite pits.
Winter is bitter and air pollution peaks then, worsened by the basin the city sits in.