It was a scorcher of a day when we visited but we hired a double bike ( 100 yuan I think) and set of around the wall it's a 15km bike ride all paved no cars or if your lazy take an electric golf cart bus. You can just ride between corner towers and enjoy regular ice cream breaks at the kiosks along the way. Allow 3 hrs to enjoy but if you just want to get up take a photo and have a shorter stroll an hour would be ok - but you would kick your self later as it's a really interesting walk. There was an entrance fee but it was so cheap I forgot was it was - maybe $5 aus????? Anyway it's worth it
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