Hokkaido is Japan’s most northerly main island, an otherworldly volcanic land with eastern Asia’s highest concentration of brown bears. One family are on their trail … in a campervan

Looking back, The Revenant was an ill-advised choice of in-flight entertainment. The image of Leo having his guts ripped out by a bear was still on my mind at 3am on our first night camping in the wilds of Hokkaido, when I finally squeezed out of my camper van bunk and tiptoed outside to the loo, twitching like a meerkat at every rustle from the undergrowth.

The noise turned out to be an especially dapper fox. Not everyone is that lucky. Japan’s bears are killers, claiming a handful of lives most years. Newspaper reports of such incidents were something else I probably ought not to have occupied myself with, before leaving with my wife and two sons for a six-day camping trip to Japan’s northernmost main island. Better known as a winter destination, Hokkaido’s staggering Lost World scenery is a beautiful place to explore in the spring, summer and autumn too. It is also home to around 3,000 brown bears, weighing up to 350kg each and twice the height of a man.

Facebook Twitter Pinterest ‘The Jurassic Park vibe transformed into absurdly picturesque farmland.’ Photograph: Getty Images

“Don’t worry, we’ve never had a brown bear attack here; it’s the black bears on the mainland [Honshu] that cause the problems,” Shinji Sato, our guide, tried to reassure us. (He’s an astro-physicist turned “Stuff Naturalist”, according to his business card.) “The black bears on Honshu tend to panic and attack humans, but Hokkaido brown bears are more shy.”

We had picked up our Toyota campervan from the island’s capital, Sapporo, three days earlier, and headed east on a circular route. After two long days of driving, our third was spent trekking – in search of a waterfall – through the forests of the Shiretoko peninsula, a wilderness national park on the island’s easternmost point, within sight of (disputed) Russian territory. Shiretoko is home to rare eagles, and its waters to various whale species; it also has the highest density of bears on the island.

Facebook Twitter Pinterest Michael Booth and family in Japan

Our van was far from luxurious, and if you’re used to camping in Europe, be warned: Japanese campsites have virtually no facilities (you traipse to a nearby onsen, or hot spring, hotel to wash), and the rules for rubbish disposal make Brexit negotiations seem straightforward. They are more like overnight stops than holiday destinations in their own right: locals bring all they need with them and set up neat tents for cooking and sleeping, and mosquito net gazebos for dining.

Facebook Twitter Pinterest Volcanic activity at Hell Valley, Noboribetsu. Photograph: Getty Images

Driving in Japan, however, is a doddle. The Japanese drive on the left and road signs are subtitled in English. Their petrol stations embody the philosophy of omotenashi, or good service, making you feel like an F1 driver making a pit stop. The Japanese are also polite motorists and stay well within speed limits. That suited me fine: all the more time to take in the staggering views of forested mountain ranges, epic road tunnels, coastal cliff roads and volcanoes steaming silently in the distance.

As we passed through the Furano valley, the Jurassic Park vibe transformed into absurdly picturesque farmland, where smallholders grow those famous £40 melons, plus tomatoes, potatoes, sweetcorn and lavender. (Our van’s limited galley meant that we mostly made do with food from convenience stores: decent takeaway sushi or instant ramen, with melon buns for dessert.) Further west, at Noboribetsu’s “Hell Valley”, the landscape turned Martian, with steaming red sands and boiling brooks.

Facebook Twitter Pinterest Brown bears at Cape Shiretoko. Photograph: The Asahi Shimbun/Getty Images

But back to the bears. Emboldened by Shinji’s reassurances, I asked if he might take us to see some. A couple of hours later, after one of the best meals of my life – freshly cooked king crab at Rausu Maruuo Hamada Shoten, a restaurant, not much more than a fisherman’s hut really, by the beach (365-1 Rebuncho, Rauso-cho, Menashi-gun) – we were crashing over white waves to the uninhabited tip of the peninsula in a sea urchin boat, basically a fibreglass tub with an outboard motor.

At first, it seemed as if we were out of luck. And then, suddenly, my younger son sprang up and pointed excitedly. There on the shore was a brown bear! We drew closer. According to Shinji it was about three years old. This muscular furball was turning over stones in search of insects. We saw another of a similar age as we hastened back to port. It was one of the Great Days, the day we saw wild bears.

Facebook Twitter Pinterest Vale Niseko Hotel

They were still the main topic of conversation three days later in Niseko when, having completed our circumnavigation of Hokkaido, we were enjoying the comforts (bath!) of the renowned Vale Niseko ski hotel , which has mesmerising views of the 1,900-metre Mount Yotei.

Here, we rented bikes from Niseko Nature School and headed out to the volcano. At one point a large snake crossed the road in the middle of our group. We stopped, and watched it slither into the lush undergrowth – not as exciting as a bear, but a moment to remember nonetheless.

• Campervan rental costs from £140 a day for a five-berth with japanrv-rental.com. The guide, car hire and hotel accommodation were supplied by Inside Japan (0117 370 9751, insidejapantours.com), which offers several trips to Hokkaido. For more information, visit the Japan National Tourism Organization (seejapan.co.uk)

The Meaning of Rice by Michael Booth, published by Jonathan Cape, is out now (£14.99)