Lake Tazawa is absolutely worth visiting. It holds the distinction of being the deepest lake in Japan, reaching a depth of 423.4 meters. The surface of the lake mesmerizes with its shifting hues, ranging from brilliant lapis lazuli to azure and indigo. Visitors can enjoy the waters by taking a relaxing cruise on a sightseeing boat or opting for more active pursuits like paddle boating, canoeing, kayaking, or SUP.