The free museum tickets vanish in minutes — buy the Tang murals instead

Shaanxi History Museum is the context for everything else in the city, and its free tickets are released online a few days ahead and gone almost immediately.

Set an alarm for the release if you want them. If you miss out, the paid Tang dynasty murals gallery is a separate ticket, far easier to get, and quiet. Either way, go before the Terracotta Army rather than after: the museum explains what you are looking at.