2.5 hours away from Chengdu lies this paradise of hiking, forest, and mountains.
This a 2.5+ hour drive from Chengdu, a city of 14 million and capital of China's Sichuan Province. Driving into Siguniang National Park you will reach Siguniang Village which is like any other touristy town in China - nothing but hotels and places to eat.
The entrance to Changping Valley costs around $15 (~100 RMB) which includes the ticket for entry and a short, round trip bus ride to the entrance of the valley. The park entrance opens around 9am and the last bus back is at 5:30pm (as of winter 2017).
The hike is very easy, and the main trail is completely on a boardwalk for the first 7km. After that the trail keeps going through the extent of the valley (~25km total) but it is hard to go too much farther and have a relaxing day trip. Camping is allowed deeper in the park after the 7km boardwalk.
For fall colors like the pictures above, the best time to go is end of October through the very beginning of November. In winter the park is still open, but very cold and is a popular ice climbing destination.