For reasons that have nothing to do with architecture, you need a police permit to stop off in YIXIAN , 60km due west of Tunxi, arranged through the CTS for about ¥50. Yixian itself is a stepping stone to XIDI (¥20 with compulsory guide), a village 10km east and reached by minibus charter - try for ¥30 return - though the Tangkou-Yixian bus also passes by here once a day in each direction. Xidi constitutes some 120 perfectly maintained eighteenth-century houses set along a riverbank, now turned into a large antiques market. It's a nice spot, however; the local dialect is suitably dated, and there are endless examples of carved gilded wooden screens and panels, as well as thin line paintings on front walls showing pairs of animals or "double happiness" characters. Mirrors placed above the three-tiered door lintels reflect bad luck or reveal a person's true character - a useful tool for judging the nature of strangers.