Mostly visited by Vietnamese tourists, the grottoes at the newly named UNESCO World Heritage Site Tráng An in Ninh Bính (once the ancient capital of Hoa Lu) offer a scenic alternative to notoriously scammy Tam Coc. A rowboat ride lasts 2-3 hours, wending past towering limestone karsts and passing through a network of nine spooky caves. The rowers, which are almost exclusively women, use both their hands and feet to steer the boat; they appreciate when riders chip in a little muscle. They’ll stop for photos anytime you signal and break as long as you like at two pagodas. The water is clean and green, with almost no rubbish, although some passengers chain-smoke cigarettes as they bob along.

Re: timing, the greenish-blue waterways are the least crowded before 9 a.m. and after 3 p.m., when all the daytrippers head back to Hanoi. Avoid high holidays, lest you want to sit in bumper-to-bumper rowboat traffic with partying Vietnamese families. FYI, if you have fewer than four people in your party, you’ll have to wait for other passengers to show up; the rowers insist on a full boat before setting out. We paid 150,000 dong per person (about $7 USD); it’s likely this was a special “foreigner” rate. Regardless, our rower worked hard and we tipped her generously. No matter when you go, the heat is brutal in these parts. Pack multiple bottles of water, sunscreen, sweat towels, and an umbrella for shade.

Tráng An, tp. Ninh Bính, Vietnam; +84-98-912-3010.