karst pillars and landscape with sinkholes

akiyoshi akiyoshidai architectural asia attractive august beautiful beauty cenote countryside daytime define destination doline earth element footpath geology grass grassland gray green hiking hill honshu japan japans karst landscape largest limestone meadow mine national natural nature outdoor park path pillars pinnacle plateau prairie pretty quasinational rock rural scenery scenic science sinkhole sinkholes stone summer tourist trail tranquility view wilderness yamaguchi