Tottori Sand Dunes look like a slice of desert dropped on the Sea of Japan, yet they take nearly 1,900 millimetres of rain a year and vanish under snow in midwinter. The sand is granite grit weathered off the Chugoku Mountains, carried down the Sendai River, spat into the sea, then thrown back onto the beach by the waves for the northwest wind to drive inland — a conveyor that has run for roughly 100,000 years. It has built a field 16 kilometres long and 2.4 kilometres wide, ridged in three parallel waves. The middle ridge is the one everybody climbs: Uma-no-Se, the Horse's Back, a crest 47 metres above the sand at its foot. Behind it the ground caves into bowls called suribachi, 90 metres from the highest rim to the deepest floor. Japan made the dunes a National Natural Monument in 1955, and they anchor the San'in Kaigan UNESCO Global Geopark.
Climb the Horse's Back — soft sand, no steps, steeper than it looks — and the far side drops straight to the water. When wind runs at five to ten metres a second across dry sand it corrugates the whole surface into fuumon, ripple patterns that form overnight and vanish under the day's first footprints. Camels wait at the entrance, boards run down the slip faces, paragliders launch off the crest, and next door the Sand Museum carves a different country out of packed sand each year. This desert survives only because people fight for it. Pine windbreaks planted from 1948 cut off the sand supply, grass moved in, and by 1991 vegetation covered some 42 percent of the dunes. Weeding began in 1994, volunteers joined in 2004, and about 75,000 of them have since pulled the invaders out by hand to keep Japan's most famous emptiness empty.