This 4.5km-long valley is forested with ancient ferns and dotted with gushing cataracts. Paths follow both sides of a river; gushing minifalls lead to four ‘proper’ waterfalls. The biggest and most impressive is the last, the 60m-high White Dragon Pond Waterfall (Báilóngtán Pùbù). You can get really close to the falls here (you can even walk behind one). The circuit takes about three hours; there are also other trails leading off the main paths that intrepid hikers will enjoy.
Sìdònggōu is the most touristy of Chìshuǐ’s sights, but still not overly crowded, even in summer. Buses run the 15km here from Chìshuǐ’s bus station (¥8, 30 minutes) hourly from 7am, and return on the same schedule.
Buses to Sìdònggōu from Chìshuǐ also pass by the town of Dàtóng (大同), which has an attractive and historic old town (gǔzhèn) quarter.