Why Izu Peninsula is a truly secret slice of Japan

Meandering along the cobblestoned riverfront, lined in cherry blossom trees, I felt a sensation that’s become increasingly rare in Japan. Among the bamboo groves and photogenic vermillion bridges, tree-cloaked temples and shops selling handmade paper, there it was: solitude.

Shuzenji, a historic hot springs town in the north of the Izu Peninsula, was every bit as charming as some of the historic corners I’d visited in Kyoto or Nara. But rather than the waves of tourists you encounter in these popular stop-offs, here there was hardly anyone at all.

It was family that first brought me to the Izu Peninsula. A brother-in-law relocating from Tokyo, looking for a countryside base within a decent commute — in London terms, a bit like moving to the Kent coast. But Kent, Izu is not.

Formed from the merging of two active volcanic arcs, the mountainous, lush and cliff-lined peninsula is a Unesco Global Geopark, sprawling over 550 square miles of dense and dramatically undulating greenery. Outside the main settlements, it is wild and prehistoric feeling. And at its heart, Martian-green punctuation point Mount Omuro — a 580m grass-lined volcanic cone — is ceremonially burned each February to maintain its distinctly luminous hue.

You might blame Izu’s wildness for its lack of visitors; in the central regions roads are few and dramatically winding, and in the west they hardly exist at all. But given aforementioned Shuzenji and the east coast is well-served by JR’s scenic Itō Line railway, I put the quiet mostly down to the herd effect. Most international tourists are so busy ticking off the “golden route” destination of Hakone, just slightly to the north, that they don’t bother looking at what’s just below.

The day I arrived from Tokyo — a journey that can take as little as 36 minutes — I trundled south down the coast along with school kids and commuters. As we began to hug the coastline, a tropical, holiday feeling dropped my shoulders. Outside the train windows the sun was shining and blue coves were strung like jewels, threaded by golden beaches, with surfers on the waves. Izu is known among the Japanese for its sublime sands, which is why so many Tokyoites escape here for holidays in sweltering July and August.

If I stayed on the train all the way to the end of line, in about an hour I’d reach Shirahama — the ace in the beach deck: broad, white and famed for its clear azure waters. Though it’s not the only south Izu draw. Nearby Shimoda is where American Commodore Matthew Perry docked in 1854 and strongarmed Japan’s entrance into international trade, effectively changing its history for ever. Monuments, a historic old town with museums, and a huge hydrangea festival in summer also pull in crowds. But today, I was getting off at more northerly Itō, where my brother-in-law’s house lay somewhere high up in the hills, a new-build among a glut of abandoned homes being slowly reclaimed by volcanic forest.

Like in much of the Japanese countryside, population decline has left parts of Izu with grand ageing buildings, and not enough people to fill them. Some, like the vast Hatoya resort, which sits on a hill overlooking Itō’s seafront, are amazing timewarps of mid-century design. They’ve become Instagrammer destinations in their own right, for those keen to capture the eerie, anachronistic serenity.

I spent a couple of hours kicking around Itō waiting for my brother-in-law to arrive, popping in for a tempura shrimp sando and draft beers with locals at a street food market, checking out the waterfront and touring the Tokaikan museum (entry 300 yen/£1.40). Built in 1928 as a grand ryokan on the banks of the Itō river and closed in 1997, Tokaikan features remarkable wood carvings, ornate glass and mid-century relics; plus onsen baths you can still use and a café on site. Creaking around the empty hallways at tatami guestrooms overlooking the river and town was equal parts fascinating and spooky.

A few streets over from Tokaikan is the KAI Itō (from £97, hoshinoresorts.com), part of the luxe Hoshino brand, where the onsite onsen is furnished with a waterfall. Meanwhile, in Shuzenji, the Relais & Châteaux-endorsed Asaba (from £474, asaba-ryokan.com) is one of the country’s most celebrated ryokan inns, showcasing traditional Noh theatre. And down the coast in Higashiizu, Onko Chishin operates Izu Retreat Atagawa Suiko (from £464, by-onko-chishin.com), where modern-minimalist rooms are furnished with private onsen overlooking the sea.

Things get rawer at Jogasaki, a half-hour drive from Itō. Here on a windy day, the ocean swirled violently against black lava rocks as I crossed the wobbly 48m Kadowaki suspension bridge. Walking trails along the coast spread like tentacles north and south. With no rain gear in tow, I decided to skip the hike and chose to scale the central lighthouse instead. Gazing out of the windows, I could pick out a spray of islands on the hazy horizon. A curve of a distant coast, I thought. I knew Tokyo was somewhere there too, waiting just beyond sight. Though it’s felt so far away these past days, I’d almost forgotten.

Book it: Inside Japan has an eight-night trip costing from £4,586, international flights excluded; insidejapantours.com