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Making a splash: The Saklikent Gorge in southwestern Turkey is one of the largest geological features of its kind around the Mediterranean. It's a popular day trip for many visiting the region.
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Flying the flag: A gigantic Turkish flag flies over the gateway to the canyon.
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Getting ready: At the entrance to the gorge there are cafes and shops renting shoes for scrambling over the rocks and through muddy waters.
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Riverside rest spot: Saklikent also has plenty of places to relax, including restaurants, hotels and camp sites.
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Safety first: Hard hats are advised for people exploring the canyon. Accidents are not unheard of, especially after heavy rain leads to flash flooding.
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Making an entrance: Visitors enter the gorge through a walkway suspended over the fast-flowing river.
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Muddy waters: Many visitors enjoy daubing themselves in mud from pools on the canyon floor, or using the mud to make rudimentary artworks on the walls.
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Going deep: While the gorge's lower reaches can get busy, fewer people venture further up where the terrain gets tricky.
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Walled in: The sides of the spectacular canyon reach up to 300 meters in some places.
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Wading in: At times, visitors need to wade through waters that come over their waist to navigate the canyon.
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Big deal: The canyon stretches for 18 kilometers (about 11 miles), but not all of it is accessible.
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Cave exploration: The route passes through cave-like chambers and involves clambering up gigantic boulders.
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Guiding the way: Guides like Salih Demirel are on hand higher up the canyon to help visitors tackle the trickier sections.
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Journey's end: A small waterfall marks the point at which visitors have to turn back.
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Sign of success: Saklikent has been a popular visitor destination since opening to the public in the 1980s.

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CNN  — 

Sometimes in the sunniest, warmest and most relaxing of places, we seek out dark, cold danger. Which – along with the kind of gasp-inducing beauty that quickly fills up your phone’s photo reel – goes some way to explaining the popularity of the Saklikent Gorge.

Saklikent sits near southwest Turkey’s “Turquoise Coast,” a beautiful stretch of the Med where most travelers are decanted from airplanes and more or less flop on the shoreline for a week or two before heading home.

Some do venture inland where, after less than an hour of driving, they come across one of Turkey’s great natural wonders – a tall and narrow opening in a sheer cliff face out from which pours the blue waters of an icy river rushing down from the Taurus Mountains.

Around 18 kilometers (11 miles) long and with walls of up to 300 meters (984 feet), Saklikent is the largest canyon in Turkey. Located in its own national park, it’s also known as the “Hidden Valley” or “Lost City.”

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A gigantic Turkish flag flutters above the entrance to the gorge.

When summer rolls around, it’s a magnet for tourists and day trippers who congregate at its busy lower reaches for a fun splash in its chilly cascades, a waterside kebab, a quick marvel at the steep canyon sides and then a ride down the river in a rubber tube.

Plenty of day tours offer Saklikent on their itineraries, with departures from the coastal cities of Ankara, Fethiye or Kaş, and smaller resorts in between. Most don’t hang around for long.

But those with time to kill and adventure in their veins can go deeper to find chasms where few tread. They’re not places for the anxious or ungainly, but they deliver adrenaline hits along with – when you’re back in the sunshine – the buzz of getting out unscathed.

‘High risk’

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Hard hats are advised in the narrow canyon, where rocks can fall from the steep sides.

Saklikent doesn’t claim to be danger free. Both before and after you enter there are large signs warning that pitfalls lie ahead. “The first 500 meters of the canyon’s walking route is suitable for children provided they’re accompanied by an adult,” they advise. “Going further carries risks of security.”

Even for grown ups, the warnings are dire. Those who make it more than a mile upriver without a guide and proper equipment “face a high risk for the safety of life and property.” While such signs keep many from exploring, others undoubtedly see them as a challenge.

At the canyon entrance, the atmosphere is festive. After buying their tickets – less than $2 – visitors pass through a narrow fissure of rock along a wooden pathway suspended over lively waters. Overhead, a gigantic Turkish flag ripples in the breeze.

This soon opens out into a broad natural basin where spouts of frigid water cascade from all sides. There are food and drink stands here, and picnic tables where people sit with their bare feet in the cold river and hands around a glass of hot Turkish tea.

There are delighted whoops and squeals from those horsing around in the benign torrents, enjoying a chilly dousing before sitting out in the sunshine to dry off. Crowds build up as the day marches on. It’s a fun, happy place – but only in good weather.

“In winter, when it rains, all this is kaput,” says Salih Demirel, one of the guides who help visitors explore Saklikent’s higher sections. He describes raging torrents smashing through the picnic area after heavy rains.

For that reason Saklikent is best avoided outside of late spring to early fall. Even in summer months, it is advisable to check the weather forecast as downpours can create problems - two people died here in July 2014 after a rare summer flash flood.

Visitors are also urged to wear hard hats, which are available to rent, though few do. Appropriate shoes are a must and are also offered for hire, but anything suitable for clambering over rocks and wading through water and mud will do.

Raging torrents

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Many visitors enjoy smothering themselves with mud.

From the picnic area, there’s an easy, flat walk along the canyon floor as it zig-zags between the cliffs. Here and there pools of water are used as mud baths by some. Others daub the gray gloop onto the rocky walls, leaving handprints and rudimentary artworks.

Then it starts to get tricky – and spectacular.

In some places, the opaque muddy water reaches right across the canyon, meaning the only way through is to wade in without knowing how deep it is. Inevitably, unsuspecting legs are plunged straight into submerged holes, bags are dropped and children, carried aloft on shoulders, grip tightly onto the anguished facial features of their parents.

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At times the marble and limestone walls close in, forcing people to scramble under gigantic and ominous boulders that have dropped from high above and become wedged in the gap between them. It can get dark too, as sunlight struggles to penetrate the narrowing fissure.

After a couple of kilometers of walking, the route enters what feels like a chamber where the only way forward is to clamber up over a series of tricky rock ledges, often with water rushing over them, and wade through deep, chilly pools.

This is the point the signs warned about.

It’s here that most people turn back. Those that decide to press ahead are advised to use one of the guides who can often be found here waiting to pick up customers. It’s not necessary to have one, but it can be useful over this potentially treacherous terrain.

“We know where it’s too deep underwater and where all the dangerous places are,” says Kadir Suyabatmaz, one of the canyon guides. “We see many accidents, we’ve had to carry out people with broken legs.”

Pushing on with fellow guide Demirel leading the way, it’s easy to see why. The vertiginous rock walls pressing in on either side and rushing water everywhere make it stressful enough even before you have to crawl up through a cascade, feeling for hand or foot holds.

Demirel points out hidden ropes and offers boosts up the steeper sections. He also pathfinds safe routes through wading pools. Eventually, the route enters what looks like a large cavern clearly carved by titanic forces over millions of years and strewn with gigantic boulders.

There’s daylight up ahead and, after a last climb over the rocks and a splash through a last shallow pool, the end of the road.

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A final clamber through a cave-like chamber leads up to a waterfall.

A small waterfall rewards those who make it here and also a low cave entrance that hints of more ahead – although it’s impossible to go further. Upper reaches of the canyon can be explored, but not from here.

It takes about an hour to reach this point – a journey that’s scary at times, but is as exhilarating as it is refreshing. The 30-minute walk back down is equally exciting, with many of the same challenges in reverse.

The gradual return to warmth and sunshine feels like a victory lap, especially when you reach the crowds near the entrance most of whom will never know the real secrets of the Hidden Valley.