Cruise the magnificent limestone karsts of Vietnam's Halong Bay on a full - day private tour adventure from Hanoi. (virtual-vietnam.com)
With emerald green, brackish waters surrounded by an impressive limestone karst formation naturally sculpted through the years by the weather, Barracuda Lake offers not only a splendid place to visit, but also one of the most original dive sites in the region. (philippines-hotels.ws)
Then travel to the dramatic limestone karst landscape of the Burren, where we'll meet a local farmer to learn about this otherworldly landscape and the traditions of its people. (nationalgeographicexpeditions.com)