Ninh Binh was our last stop before reaching Ha Long Bay, and it only had a couple of things to do, but they were good. The coach dropped us and our bikes off at 3am so arriving at the hostel was a bit grim, but they were very nice about letting us in that late.
Trang An Secret Garden: It was slightly more than a hostel but not quite a hotel. It had a nice decked bar on the upper balcony and a big pool in the back. Very relaxed vibes, definitely not a party hostel like some previous ones.
Ninh Binh is home to a sort of Ha Long Bay on land. Huge limestone hills, a bit like in Phong Nha, with rivers going around and through them. You can get a boat ride through them, driven by a local. At the end of the trip they take you to some floating salesmen who sell some very expensive refreshments, but they insist on you buying some food. That plus the tip we gave at the end made it a bit more expensive, but still >$20.
These locations are called Trang An or Tam Coc. I visited Tam Coc but as far as I know they are similar.