Visit this secret Slovenian lake for a quiet summer break

“The best advice I have for visitors to Slovenia,” says Jaša Zidar, stroking his goatee and staring out at the distant peaks, “is to get to Lake Bled and keep on driving.” It’s not that the outdoor guide doesn’t find the country’s most famous natural landmark — with its exhaustively photographed, church-adorned island — beautiful. It’s more a question of geography.

Bled sits in a glacial valley. Pass it and follow the road that traces the valley floor for a further half-hour until the road ends and you can’t drive anymore, and you’ll find yourself on the shores of its sister lake, Bohinj — Jaša’s workplace. He’s a guide and leader at the activity centre midway along the southern shore, and he’s certainly in the right place for his line of work.

Bohinj may fall within strictly protected Triglav National Park, but it’s not a landscape to simply admire from afar. Mountain biking, cycling, paddleboarding, rock climbing, hiking, diving, canyoning and caving are all on offer here, immersing you in one of Europe’s most stirringly scenic landscapes. I’m starting gently, with a few hours canoeing in the lake’s crystalline waters. Jaša gives me a briefing, a buoyancy aid and a dry bag, and helps me launch into the water. Within a few dozen languid strokes, I find myself in the centre of this vast body of water, lit by the slanting sunlight of a bright spring morning.

Bohinj (the ‘j’ is silent) extends nearly three miles east to west and is ringed on three sides by a steep limestone escarpment. Beyond this — their snow-capped peaks shimmering in the haze — are the Julian Alps, and the three-pronged, 2,864-metre mountain that it’s said one must ascend to be considered a true Slovenian: Mount Triglav.

As I paddle, I can make out hikers on the perimeter trail and the sun blinks with paragliders, circling like watchful raptors hundreds of feet above. A slender spire draws my eye to the eastern tip of the lake and the hub village of Ribčev Laz. There, at the water’s edge and beside the double-arch stone bridge that spans the lake’s outflow, stands the 11th-century Church of St John the Baptist. I paddle close enough to make out the faint smudge of the paintings of St Christopher on the exterior, some of which have withstood the elements for seven centuries.

Returning the canoe and reclaiming the e-bike I’ve hired for the duration of my stay, I cycle to the lake’s western tip. From afar, one could be forgiven for thinking Lake Bohinj is ringed by sand directly imported from the Caribbean. The creamy white fringes are, in fact, finely ground limestone left by the glacier that sculpted the valley’s extravagant proportions. It gathers in coves and protrudes into the water in inviting peninsulas.

I watch a family spread their towels and brave a quick, bracing dip. Three times a year, Lake Bohinj is replenished entirely from meltwater and underground springs — far more often than Lake Bled, or so one local tells me with a note of pride that hints at a quiet rivalry. This meltwater is great for clarity, less so for swimmable temperatures, though in summer the top few surface inches can sneak above 20C.

The lone, glass-bodied electric launch — a small passenger boat — that soundlessly plies the lake in summer is just docking at the water’s edge campsite as I pass. Pushing on, I lean on the bike’s battery-assist to pedal a mile or so further, up towards the Savica waterfall. It’s meltwater season and can be heard long before it’s seen, a deafening sound like an eight-lane highway. The water plummets more than 230ft in two discrete torrents that merge in a pool of alluring aquamarine.

A couple of mountain huts stand nearby. I sit on the terrace of Koča pri Savici (Hut by Savici) with a coffee and a plate of flakey apple strudel and watch the hikers pass, setting out on the steep trails that begin here and wend their way up to the Alpine peaks and plateau lakes far above.

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It’s tempting to join them, but the promise of a slow evening back at Hotel Bohinj — stylish and timber-hewn, set just behind the lakeshore in Ribčev Laz — calls. From the bubbling outdoor pool of the spa, I plot my route up the flanks of Vogar, the gentler peak rising in the lake’s northwest corner, for the following day.

At dawn, I set out to climb it, cycling a mile north to the rural hamlet of Stara Fužina before continuing on foot up a steep, forested track, dappled with sunlight. For an hour or more, the lake remains concealed. Then, at a small sign to the left, I step out from the treeline into an immense panorama. Far below, the full expanse of the lake — a deep metallic blue, where it reflects the facing mountains — is eerily calm. The tiny electric launch cuts across its centre, like a skate tracing ice, its wake fanning out in serene symmetry.

I’m just about to leave when a paraglider appears. He nods a greeting before unfurling his canopy and lines, laying them out methodically on this slender roof terrace of grass, and doing his final checks. Then he rushes the precipice with a flurry of urgent footsteps, catches a thermal and glides out into the Alpine air. Energetic and tranquil, it’s Lake Bohinj all over.