Two and a half hours. Guo Tu took Metro Line 4 in Huang Zhuang, Haidian, changed to Metro Line 10, and got off at Peony Garden Station. Take the southeast exit and walk eastward to a bus stop under an overpass. There is bus No.345, get off at the terminal Changping Dongguan, and transfer to bus No.314 to Dingling and Changling. If you want to go to the Ming Tombs Reservoir, you can take bus No.56 or No.23 from Hong Xiao at Dongguan, and see the stop sign and route clearly.