We had a terrific time biking the wall and highly recommend it! The entire wall is easily doable in less than 90 mins, counting all our photo stops and bathroom visits. There are wonderful views of old architecture mixed w/ new and even temples you get a bird's eye view of. While the smog was troubling, even that is photogenic. The pavement varies in how well it's been maintained, which makes parts of the ride rather jarring, and we were glad we were padded! The bikes are comparable to boardwalk bikes; be sure you take extra cash for a deposit.
The young staff at the entrance very firmly--and with pleasure--informed us that their Student rates were Only for Chinese students, not for US, although our daughter's ID had been accepted everywhere else we'd visited in China, from the Great Wall, to the Terracotta Warriors, to museums in Shanghai. Hmmm.
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