My little walks into the mountains of Nikkō National Park last weekend only whetted my appetite for the outdoors, so this weekend I planned a longer trip to Chichibu Tama Kai National Park northwest of Tokyo.

I left my apartment in Wakō first thing Saturday morning. Two train lines and a bus later, I was at the bottom of Mount Mitsumine.

It was 10 in the morning. We are still in the rainy season and the mountains’ thick green forests disappeared into equally thick clouds. I rode a gondola up to Mitsumine-jinja, a 2,000-year-old shrine that’s served as a home for priests, pilgrims, and mountain ascetics. The shrine’s two main buildings were being renovated when I got there, unfortunately, so I only saw the inside of one of them.

I wandered the grounds and photographed the other holy buildings, then set out for my real destination, 6,617-foot Kumotori-yama. The trail from the shrine to the peak would take me over two other summits, rising 3,000 feet in six miles.

I would spend Saturday night in a mountain hut near the summit; all the gear I needed for this overnight trip was a bookbag with two lunches and some water in it. One the way, I passed two Japanese men who were going to camp on the mountain. They had big boots and fully-loaded backpacks. They were going much more slowly than I was.

“Konnichiwa,” I said.

“Konnichiwa,” they responded. Then, to each other: “Hayai desu ne” (he’s fast, isn’t he?).

As in Nikko, the mountains were geologically young. At times the ridge was only a few feet wide, steeply sloped for thousands of feet down both sides, its dense forests fading into the fog.

I started in forests of oak, maple, and beech. Cicadas buzzed everywhere. Sasa grass, a dwarf bamboo, completely filled the understory. Despite being called a “dwarf” bamboo, it was over six feet tall. I could not see through it when it lined the trail. At higher elevations, I reached forests of spruce, larch, hemlock, birch, and Veitch’s and Nikko fir. There were also cypress and cedar.

The gondola I’d ridden up to the shrine had taken me into the clouds, and I sincerely hoped that the hike up to Kumotori-yama would take me above them. Only after hours of walking through thick fog did the sun start to light up the tree leaves, but the above sky never quite cleared.

I had dinner and a place to sleep waiting for me at the hut, Kumotori Sanso. The hut was newly renovated, but in a traditional Japanese style. The owners didn’t speak a word of English (a Japanese friend had helped phone in my reservation), so I had a lot of trouble trying to explain to them what I was doing there. Fortunately, a man in the lobby spoke both Japanese and English and helped me settle everything quickly.

Once I took off my boots, there was a confusing hierarchy of three sets of slippers for me to navigate: one set for inside the hut, one set for outside the hut, and a final set for the outhouse. I was reprimanded with a sharp “No!” from the manager when I made the faux-pas of putting an “outside” slipper on the platform that was only for socks or “inside” slippers. I don’t think he knew many other English words. I kept trying different combinations of slippers and floors and the manager kept yelling “No!” at me until I found the right one. As one would expect, despite the mud covering everyone’s boots, the floors inside the mountain hut were perfectly clean.

The sleeping arrangements were also traditional: the floors of the rooms were covered in tatami. There were no beds. Instead, the bedding—soft mats, thick blankets, and little rice-husk-filled pillows—was kept in the closet. Everything came out at bed time and went back in the morning.

I had over an hour until dinner, so I made the 20 minute walk up to the summit of Kumotori-yama. It is the highest point in Tokyo and one of the 100 famous mountains of Japan. From the top, I could see some other ridges, but the clouds were just below the summit, and by the time I turned back I was hiking in the fog. I ate dinner with the man who’d helped check me in, Alistair. He was British but had been living in Japan for 8 years. He had a Japanese wife and was currently working as an editor for Dow Jones Newswires. He was hiking with his friend, Hase, who was Japanese and spoke a bit of English.

I finished eating. Through the window I could see that the clouds had dropped and that the sun was about to set. I finished my beer and went outside. I’d make another trip to the summit  to watch the sunset. I climbed as fast as I could. My stomach, full from dinner, cramped up.

But the view from top was worth it. Earth’s shadow was rising in the east. The clouds were much lower now: dark spines of distant ridges crested above them. On the horizon, rising to nearly 13,000 feet across a sea of unbroken clouds, was Fuji-san, its sides pastel blue and its summit swirling with pink clouds. The high clouds overhead glowed orange as the sun set and lit them from below. Everything glowed with a subtle orange light.

I was alone on the Kumotori. No one, it seemed, had thought to go up there but me. Their loss. A group of sika deer browsed nearby, occasionally raising their heads to see what I was doing.

But then I remembered: “He who watches sunsets on mountain tops walks down in the dark.” I didn’t have a flashlight with me, so I made a quick retreat back to the hut.

The hut’s lights went off at 9 and came back on at 4. Breakfast was at 5. I had grilled fish, miso soup, rice with a raw egg mixed into it, and some pickled vegetables. Alistair and Hase were taking the same route today that I was, so we decided to walk together, leaving the hut at 6. I was happy to learn that they had much better directions than I did.

Sunday’s hike was 14 miles along a ridge and over three more summits, finishing in Okutama, where we could catch a train back to Tokyo.

The first part of the hike was great. We were well above the clouds, it was cool and sunny, and there were plenty of exposed areas on the trail with good views of the surrounding mountains.

On the way down, in a steep, foggy ravine, we happened upon a group of Japanese macaques. Their little pink faces poked out from the tree branches as they yelped and barked at us.

The descent of over 3,000 feet was a little tough on my knees. We went back into the clouds and then below them. It was far more humid and warm near the bottom. There were a few rumbles of thunder.

Alistair and Hase were going to an onsen afterward and asked me if I’d like to come with them. I’d had onsen, a traditional Japanese bath in hotspring water, recommended to me plenty of times, so I accepted.

We got an hour in a private tub for about $5 each. We showered before getting in—it’s unimaginably rude to enter the tub without cleaning yourself first. The windows were open, the onsen water was hot, and it didn’t take long for me to start sweating. I needed to cool off, so I got out and took a quick cold shower. Once I was cold, I got back in. That felt great. I did it a few more times until our hour was up.

After the onsen, we stopped at a bar for drinks and then got on the train back to Tokyo.