Shang-Tu
From Tardis Wiki, the free Doctor Who reference
Shang-Tu, aka Xanadu, was the location of the Kublai Khan's summer palace in 13th century China. (TV: Marco Polo). The city was in same location as the contemporary city Duolun Naoer (多伦淖尔). A rider from Shang-tu would have to traverse one thousand miles to reach the Doctor's party in Gansu province.
