view landscape danau toba lake and tao batak toba caldera supervolcano at tomok village hill and sipiso piso mountains in

asia batak beautiful canal country countryside danau destination environment hill idyllic indonesia indonesian island karo lake landmark medan mountain natural nature ocean outdoor piso pond reservoir river rural samosir scenery scenic sea sightseeing simanindo sipiso sipisopiso sumatera sumatra tapanuli toba tomok tourism tourist travel trip tropical valley village volcano water