The scenery at this inland version of Ha Long Bay is possibly even better. The same limestone karst structures rise up out of bright green rice paddies and you get rowed through on a little boat. It is quite touristy, but much less so than Ha Long Bay - make sure you get there first thing in the morning though, before the big coaches arrive. The best way to visit is to rent a bicycle in Ninh Binh and get them to show you the lovely backroads around the area.
Near Ninh Binh, about an hour south of Hanoi on main highway (buses will drop you there).
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Definitely agree - I thought this area was stunning. We hired motorbikes and drove from Tam Coc up to Hoa Lu through the limestone cliffs - although we got lost a fair few times the day was truly spectacular.
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