Lofty lochs: understanding Scotland’s deepest lochs

So, what is the deepest loch in Scotland? Loch Morar in the Lochaber area of the Highlands takes the crown. At its deepest point, the loch reaches depths of around 310 metres – deeper than most of the seabed off Scotland’s west coast! That’s the same height as The Shard building in London (the tallest building in the UK), or about 69 Great White Sharks stacked from nose to tail. Not only is Loch Morar the deepest loch in Scotland, but it is also the third deepest loch in Europe. Loch Morar has plenty of safe entry points for wild swimming and watersports, but many swimmers prefer to take advantage of the white sandy beaches and crystal blue waters of the nearby Silver Sands of Morar. 

Did you know? According to local legend, it is even home to a mysterious creature known as Morag, who is said to resemble Loch Ness’ Nessie. 

Not only is Loch Ness perhaps Scotland's most well-known loch, but it is also Scotland's second-deepest loch and our largest loch by volume. Just how big is Loch Ness? Well, at its deepest point, Loch Ness is around 230 metres – about the same height that the Golden Gate Bridge in San Fransisco, California, sits above water! You would also have to stack about 65 Adult African Elephants (with an average size of 3.5 m), one on top of the other, before reaching the bottom of Loch Ness. Let's hope Nessie, the Loch Ness Monster, welcomes guests!  If you fancy going wild swimming, we recommend Urquhart Castle on the west side of the loch. Visitors can enjoy a day dipping in the loch as the Scottish sun beats down through the castle ruins. Having undergone a £1.5 million refurbishment, make sure to also check out The Loch Ness Centre when it reopens on 10 June. There is even a brand-new tour to enjoy - not to be missed!

Did you know? Loch Ness contains more freshwater than all the lakes in England and Wales combined!   

The third deepest loch in Scotland is another one of the country's best-known lochs, Loch Lomond. Loch Lomond sits significantly further south than Loch Morar and Loch Ness, just around 30 minutes from Stirling and Glasgow. Loch Lomond is about 190 metres at its deepest point, or the equivalent of stacking two of New York's Statue of Liberty monument on top of each other before reaching the bottom! For a more everyday comparison, that's about 190 washing machines stacked on top of each other. For those looking to venture into open water swimming in Scotland through an organised event, Loch Lomond also has an annual swimming event that takes place every September called Go Swim. The event is an excellent way to experience wild swimming, regardless of swimming level, safe in the knowledge that you're surrounded by experts. When exploring the waters of Loch Lomond, visitors should be mindful of the steep drops close to the shoreline.

Did you know? Interestingly, Loch Lomond is also the biggest loch in Great Britain by surface area, spanning a whopping 71 sq km and 36 km long.

The Scottish loch with the easiest name to remember (or most unoriginal name) is Loch Lochy. It is the fourth deepest loch in Scotland and is located in the Lochaber region of the Highlands. At its deepest point, Loch Lochy reaches depths of approximately 162 metres; that’s about the same as four Boeing 737-800 planes (at around 40m each) stacked from tail to nose! Or approximately the same as a tower made of 16,875 standard LEGO bricks. Nearby to the lighthouse on Loch Lochy, there’s a lovely stone beach that makes for an excellent entry and exit point for wild swimming in the freshwater loch. 

Did you know? Early Gaelic translations of the name ‘Loch Lochy’ roughly translate to mean ‘loch of the dark goddess’. 

Loch Ericht is the fifth largest loch in Scotland and sits on the border between Perth and Kinross and the Highlands. With a maximum depth of about 156 metres, Loch Ericht is roughly as deep as the Blackpool Tower is tall! The loch's depth is also the same as 54,167 £1 coins stacked on each other – wow. The village of Dalwhinnie is renowned for its malt whisky distillery. Travelling visitors can easily access the loch from Dalwhinnie's railway station and pick a spot for swimming (or admiring) on one of the many little beaches just off the pathways that surround the loch. Why not head for a wee dram after plunging in the cold waters of Ericht to warm up?  

Did you know? Compared to its length of around 23.3 km, the loch is relatively narrow, coming in at about 0.80 km wide at the widest point. There is also a dam that sits at the northern end of the loch that protects the quaint village of Dalwhinnie from flooding.   

Loch Katrine is located in the heart of Loch Lomond & The Trossachs National Park and is Scotland’s sixth deepest loch. Reaching depths of about 150 metres, Loch Katrine is as deep as the iconic Spring Temple Buddha statue in China is tall. Similarly, looking for comparisons closer to home, you would need to stack about 131 highland cows before reaching the same height as the depth of Loch Katrine. What a sight that would be! Loch Katrine supplies clean water to 1.3 million people across Greater Glasgow and west-central Scotland and the aqueduct that supplies the water was opened by Queen Victoria in 1859. To this day, is regarded as one of the world’s most remarkable feats of engineering. Swimming in the loch is permitted as long as staff at Loch Katrine are aware of it and swimmers stay away from the cruise routes. If you prefer to stay on dry land, hire a bike from Trossachs Pier at Katrine Wheelz. The lochside cycle route is the perfect way to take in the mesmerising views.

Did you know? The loch has also been used as a filming location for the globally famous series, Outlander.   

While Loch Tay is the seventh deepest loch in the country, it's the largest in Perthshire and, at its deepest point, reaches depths of around 150m, making it a close contender for sixth place with Loch Katrine! At its deepest point, you could stack more than two of India's glorious Taj Mahal buildings on top of each other. You could also stack 27 adult giraffes before you would reach its depth. For those looking to balance the harsh elements of wild swimming and watersports on the loch with a bit of R&R, the Taymouth Marina Spa has a slide from their onshore facilities directly into the loch's chilly waters. If that's not enough, Unique Adventure Tours Scotland offer private half-day or full day Stand-Up Paddleboarding sessions.   

Did you know? Ancient settlers once lived upon the loch, inhabiting artificially created islands that are known as Crannogs. The Iron Age settlers built the Crannogs in around 2000 BCE, and while there are about 18 crannogs upon Loch Tay, most of them are now submerged. However, a large Crannog can still be found on the north shore of the loch at the Scottish Crannog Centre.

Loch Rannoch in the Perthshire region of Scotland is our eighth deepest loch, with the deepest recorded depth at around 130 metres. That's about the same in depth as the London Eye is in height. In comparison, that's also roughly the same as about 30 average-sized double-decker buses stacked! Much like Loch Tay, Loch Rannoch is also home to a Crannog (artificial island) that was used in the 18th century as a base for the outlawed members of the MacGregor Clan. The expansive sandy shores of Loch Rannoch mean you could easily have miles of the watery world to yourself. However, for those who are perhaps less experienced in plunging into cold waters, Loch Rannoch has plenty of watersports opportunities where an expert can support you.    

Did you know? Loch Rannoch is also an excellent place for wildlife spotting, with animals such as red squirrels, pine martins, otters, capercaillie, and red deer in abundance in the surrounding Rannoch region. 

Scotland’s ninth deepest loch, Loch Shiel, comes in at about 120 metres in depth – or about the same height as the Glasgow Tower that towers over the city of Glasgow’s skyline. For any basketball fans out there, that’s roughly the same as about 64 professional NBA players stacked! And what’s a Scottish loch without a resident monster? Loch Shiel is said to be home to a mythical creature known as Seileag. Seileag is said to be an enormous eel that lived in the ocean but sometimes entered the lochs. Loch Shiel stretches as far as the eye can see, and the mountains tower steeply above the shores, meaning exploring it by water will give you a whole new perspective to take in its awe-inspiring beauty. 

Did you know? The loch has been used as a backdrop of the Hogwarts school in the Harry Potter films and for the scenes where the characters are at the ‘Black Lake’. For those looking to explore more of the Harry Potter filming locations, check out our film and book itinerary.  

Loch Maree might just be our most beautiful loch. With a maximum recorded depth of 112 metres, Loch Maree is about the same in depth as two Leaning Towers of Pisa in Italy would be in height, if you could stack two on top of each other. Or, about the same as 991 cans of soda stacked on top of each other. Tollie Bay on the loch is a favoured spot for wild swimmers and watersports enthusiasts, but Loch Maree’s real water attraction lies in its scattered islands. The islands on Loch Maree are some of the least disturbed by human places in the UK, and, as such, the habitats of the island support many extremely rare species of plants, insects and birds. For those looking to paddle over to the islands, it is crucial to do so responsibly in line with the local access guidance to minimise impacts on the protected wildlife.  

Did you know? Loch Maree is another loch said to be the home of a monster, so wild swimmers should beware! Muc-sheilche (which loosely translates to “turtle-pig”) is said to live in the Loch Maree and the nearby lochs.   

Last but by no means least, we have Loch Arkaig. Tucked away between Fort William and Inverness, it is Scotland's eleventh deepest loch. Loch Arkaig plunges to depths of roughly 91 metres and is as deep as the Forth Bridge is at its highest point above water. For scale, this is approximately the same as 7,267 Jenga blocks stacked! Arkaig is a hidden gem tucked away off the beaten track with many water wellness experiences for visitors to enjoy. Wild swimming explorers can dip into the loch or head to explore the waterfall at Cha-aig to plunge into the chilly waters of one of the waterfalls' pools. 

Did you know? Rumour has it that Loch Arkaig is home to some hidden treasure. In 1745, seven caskets of gold came to Scotland from Spain to finance Bonnie Prince Charlie's Jacobite uprising in Scotland. But by the time the gold arrived, the war was already over.