Fire and water collide in Daisetsuzan. Two massive volcanoes pin the national park at the center of Japan's northernmost island, Hokkaido, their steaming peaks(冒着蒸气的山颠） dropping off into forested, snow-pillowed(白雪覆盖), river-washed(河水冲刷) slopes—half a million acres (公顷)churned(被搅和) green, orange, red, and white by the seasons(随着季节).

Japan rose from the sea in seismic violence(地震的暴力). Tectonic plates(构造板块) slid and were subducted(隐没), mantle rock melted(风化层融化) and pooled underground(地下堆积), volcanoes erupted. Quiet for centuries, Asahi Dake(旭岳), the highest peak in Hokkaido, rises to the north. Tokachi Dake(十胜岳), to the south, last erupted in 2004. In the cold, wet climate of Hokkaido, summits built by Earth’s internal fires draw snow(从地球内部的烈焰中诞生的山峰会带来降雪), and snow turns to rushing water(流动的水), forest, moss, and flower. Daisetsuzan means "big snow mountain."

Thick ground cover(植物) makes much of Daisetsuzan impenetrable(无法进入), a self-preserving preserve(保护区), untrammeled(完全无拘无束) except for the few specified trails(步道). In a crowded island country—one of the most indus trialized and densely populated in the world—the park offers rare open space, its peaks and forests bounded by neatly cultivated fields(精心耕作的田野). The park is a haven for deer, birds, hares(野兔), and bears as well as trees, shrubs(灌木), and flowers. Japanese backpackers(背包客) move in silent respect(无声的敬意) through the massif.

Occasionally in the summer and fall, Michiko Aoki(青木伦子), the daughter of a Buddhist priest(住持), hikes eight hours up and over Asahi Dake, crosses a windy ridge(多风的山脊), and descends into a secret valley to visit her boyfriend, who helps monitor the park's Hokkaido brown bears.

Early on a warm autumn day, I join her. As we approach Asahi Dake, the hollow breathing of volcanic vents tells us there is a mountain ahead, but, cloud-wrapped, it eludes us(从火山道传来的低沉声音告诉我们前方有一座山，藏在云深不知处). In the mirrored face(如镜的水面) of a pond called Sugatami-ike(姿见池), a distant patch of snow mingles(交融) with steam; strings of steam tie Asahi Dake to the kamuy, the Ainu spirits(阿依努神灵) that live everywhere.

During the glacial maximum 18,000 years ago, Hokkaido was linked by land bridges to Asia, not Japan, and the ancestors of the Ainu people crossed to Hokkaido. Few indigenous Ainu remain, their forebears having been dispossessed and assimilated by the Japanese. Yet it is impossible to look at these rivers and mountains without thinking of their sacred view of the place.

The Ainu divided their lands into village gathering grounds, or iwor, where they fished for salmon, hunted bear, and gathered wood and berries. The living things that sustained them were gods in disguise, spirits visiting the earthly world. Kamuy came as inanimate objects as well: hunting knives and bamboo houses. To return kamuy to the spirit world, the Ainu performed rituals, with gifts of food and prayer. Their central ceremony honored the bear—provider of food, fur, and bone for tools. They called Asahi Dake peak Nutap-kamui-shir, which means "the god mountain which contains the inside area of the bend of the river."

Asahi Dake used to be a perfect cone, but an eruption long ago blew out its flank. The path skirts a chaotic cleft torn by eight sulfur-collared vents issuing steam. An 80-year-old man coming off the mountain tells us that during World War II people gathered the yellow mineral for gunpowder. Michiko and friends, a more fortunate generation, ski the concavity in winter. Now the path is steep with lingering patches of snow. Above, cloud swallows mountain; volcano swallows cloud. Finally the top of Asahi Dake stands clear.

Weekend hikers crowd the summit. They eat ham sandwiches and rice wrapped in seaweed, drink cold tea, and rest rock-sore feet. Fewer come here than to many of Japan's 29 national parks, far fewer than to Mount Fuji. That iconic peak draws a hundred million visitors a year. Daisetsuzan sees just six million, many of whom arrive by bus to soak in autumn's colors. Others test themselves on the slopes of Asahi Dake.