九洞天（六仲河）为贵州省级风景名胜区，位于纳雍、大方两县交界处，全长23公里，面积150平方公里。六仲河自西向东流经两县，上段为总溪河景区段，为九洞天景区，河水在两县交界处潜入地下，称为瓜仲河伏流，长约7公里。由于这一地区河床地质为两亿多年前的沉积石灰岩，经过漫长的地壳构造运动以及地下水地表水的冲刷和溶蚀作用，地质岩体中喀斯特发育形成溶沟、溶槽、落水洞、伏流、石林、天生桥等一系列大型岩溶构造地貌景观。伏流下游，大自然鬼斧神工，在乌蒙山脊柱上开凿了九个巨大天窗。九洞成串珠状相连，洞内平均高度约80米，最高处约100米，水面最宽处约50米，最窄处约10米。九个洞天内岩溶高大雄奇，景观丰富。瓜仲河地下溶洞电站就修建在瓜仲河第二段伏流出口处的天然大溶洞内（引水式）。装机容量一期4×400KW，1984年4月投产发电，第二期2×500KW，1994年11月投产发电。电站发电厂房及全部水工建筑物、输配电设备都布置在大溶洞内，非常奇特壮观。是我国和世界罕见的天然溶洞电站，水利建设者利用天然的洞穴空间巧妙的修建如此规模的地下建筑，堪称世界水电建设的奇观。前不久经中外溶洞专家联合考察，评价该洞天为"地下的岩溶景观与地面的岩溶形态相结合，胜过世界上任何景致"；"是世界岩溶学的一本完整教程"；"风景资源与能源资源相结合，非常值得开发。"

   Situated on the upper reaches of the Wujiang River and Located in the southwest of Dafang County, Jiudongtian (Nine-sky-window) Cave is an underground water cave with nine sky windows (nine holes through which one can see the blue sky). A boat can take visitors into the cave to enjoy seeing the magnificent views inside. Covered with flourishing plants, the whole river is 23 km long with splendid cliffs along it. Sometimes, groups of monkeys are seen gamboling on the cliffs. Go boating down the river, and tourists will enjoy the drifting trip and the beautiful valley. A huge hydropower station is built there with a generating capacity of 4 x 400 kw in the first phase, 2 x 500 kw in the second phase. It was selected one of the provincial scenic spots. The hydropower station began to generate electricity in 1994.