Karatsu is a coastal city on Japan's Kyushu island. The reconstructed 17th-century Karatsu Castle offers bay views. Thousands of pine trees form the nearby Nijinomatsubara pine grove, first planted in the 1600s. The Kawamura Museum displays both Western and Japanese art, with a special focus on the early-20th-century painter Shigeru Aoki. To the north, at Nanatsugama, is a series of basalt caves carved by the ocean.