BENEATH the ruins of Duntulm Castle in Skye, a rocky tidal platform juts out into the waves. At first glance its pitted and pockmarked appearance, slightly raised above the boulder-strewn beach on the Trotternish peninsula, is nothing special, a typically sea-ravaged scene.

Yet upon closer inspection there is a pattern among the potholed cracks and crevices that line the surface. They crisscross over one another, zig-zagging across the vast sandstone and limestone slab. Some have distinct toe shapes. On dustbin lid-sized feet. Welcome to the “dinosaur disco”.

It was here that a team of Edinburgh University scientists discovered the largest trackway of dinosaur prints ever to have been found in Scotland. They belong to sauropods – distant relatives of brontosaurus and diplodocus – and date from the Middle Jurassic period.

The 170-million-year-old footprints exist in several layers of rocks that formed from sediments at the bottom of what was once a shallow saltwater lagoon.

Palaeontologists Dr Steve Brusatte and Dr Tom Challands had been working on the beach with a group of students in April 2015 and it was only while packing up their kit at the end of the day, that a curious-looking depression in the rocks made them do a double take.

Earlier that afternoon, they had spotted a similar shape on another part of the beach. “We looked at each other and thought, ‘That’s odd,’ but didn’t say anything at first,” recalls Brusatte, who coined the phrase “dinosaur disco”.

“Then we saw another one. We stopped and started to look around and noticed there was a lot of them. “They look like potholes or little tidal pools. That isn’t too surprising because you are in a tidal zone, but what we began to notice is that there seemed to be a pattern.

“There was a bit of a zig-zag, this left-and-right sequence. They were all of the same size, which would be peculiar if you just had random tidal erosion.

“Then we noticed there was some sticky out bits, way up near the tideline where the boulders meet the rock platform. There were bits of limestone sticking up like pedestals. They were also pretty consistent in size and shape.

“We could see that some of them had little bits sticking out from one side and we realised those things were toes. Then it all came together and we realised they were footprints.”

The duo and their team had spent hours crawling on hands and knees with magnifying lenses, combing the rocks for miniscule fossils. It was only when they stepped back and viewed the shoreline as a whole that the realisation struck they were walking in the footsteps of dinosaurs.

“We frantically called the students back,” says Brusatte. “Everyone started looking all across this platform and we began seeing more and more. All day we had been looking for the little things and not really looking at the big picture.

“You need to be standing back because these are big prints. If you had a hundred car tyres littering the landscape, for example, you might notice them if you were down in the dirt, but you would need to take a broader perspective to see if those car tyres had any kind of pattern.

“There were some of the prints that we could see in cross-section within the rock. It wasn’t like scour from the tides; these things had deformed many layers of rock. That meant they had to have been made when the rock was not yet rock and was still sand or mud.”

The discovery is among a growing number that has earned Skye its reputation as Scotland’s Jurassic isle. Fossils from the Middle Jurassic period, roughly 174 million to 163 million years ago, are extremely rare and the area is one of the few places in the world where they can be found.

To date, the rich dinosaur fauna of Skye has been found to include both carnivorous theropods, such as the megalosaurus, as well as herbivore species such as stegosaurus and cetiosaurus, a stocky sauropod dinosaur whose name means “whale lizard”.

A short drive down the coast on this north-eastern tip of Skye lies An Corran beach at Staffin where most days eager tourists can be found scrambling over slippery seaweed-covered rocks in the hope of spotting dinosaur prints.

When I visit it is a fairly international group – Germans, Danes, Swedes, Americans, French and a handful of Scots, myself included – who are keeping eyes peeled in search of the three-toed impressions left by a family of megalosaurus 165 million years ago.

The trackway here was first uncovered following a winter storm in January 2002. Local hotelier Cathie Booth found a footprint on a loose piece of sandstone while walking her dog along the beach and took it home to show her husband Paul.

It turned out to be from a plant-eating ornithopod, but when Paul Booth returned to the beach with Dugald Ross, who runs the nearby Staffin Museum, and Dr Neil Clark, curator of palaeontology at the Hunterian in Glasgow University, they discovered 15 to 20 megalosaurus footprints.

These ranged between 30cm and 55cm (12in-22in) in length and belonged to a formidable creature which would have stood up to 3m (10ft) tall.

“We were lucky because around that time there had been boulders removed from the shoreline when the new Staffin slipway was being built,” says Clark. “It is thought that changed the dynamics of the current and washed a lot of stuff off the beach.

“January and February are probably the best time to see these footprints. During the summer they tend to get covered in sand and slime.”

It was 20 years earlier that Scotland’s first dinosaur remains – a single footprint – were found in Skye. Discovered by Dr Julian Andrews and Professor John Hudson in 1982, the 49cm (19in) print is believed to have been made by an iguanodon-like ornithopod.

A decade passed before the next discovery. Like buses, they then arrived in quick succession. In 1992, German collector Matthias Metz discovered a small fossil partial tibia of a theropod near Elgol in the south of Skye.

Around the same time, Lachlan Scott-Moncrieff found a fragment of bone near his home in Staffin that turned out to be from a sauropod dinosaur, similar to a cetiosaur.

BP geologists Dr Doug Boyd and Dr John Dixon came across a more substantial bone on the foreshore at Valtos near Staffin in 1993. Ross led a team to recover it and sent a photograph to Clark who promptly hotfooted to Skye for a closer look. It marked their first collaboration.

Today, in a quiet corner high above the exhibits in the Hunterian, Clark takes up the tale. “There was about a third of the bone in the rock and the rest was missing,” he recalls. “You could see the impression from where the bone had come out of.”

What happened to the rest of the bone – part of a sauropod limb – posed a mystery. Had it fallen out the cliff and was lying elsewhere on the shore? Or had someone deliberately taken it? The chisel marks on the rock indicated it was likely the latter.

Although, as Clark surmised, its removal may not have been deliberately malicious. “These large sauropod limb bones, if you look at them in section, they look like tree rings,” he says. “Someone could easily have mistaken it for a piece of fossilised wood.”

During his stay, Clark learned of another bone found on the same beach that was in the possession of a local restaurant owner. Piecing it together with tiny loose fragments of the recently discovered bone, he and Ross concluded that it came from the opposite end of the same limb.

Which left just the gaping hole in the middle of the bone. The publicity that followed the discovery saw a parcel arrive anonymously at the Hunterian: it contained the missing piece. “In the accompanying letter they said they did think it was a bit of a tree rather than bone,” says Clark.

Sadly, he says, the end piece belonging to the restaurateurs has since become unaccounted for after they left Skye for Seil near Oban. “I hope that eventually it might find its way back to the Staffin Museum to be rejoined with the rest of the bone so then we would have the complete thing.”

For dinosaur fans visiting Skye, the Staffin Museum is among the must-see attractions. Founded by Ross in 1976, it has evolved from offering highlights of local archaeology and crofting history to showcasing a substantial fossil and dinosaur-themed collection.

It is a passion which took root early in Ross’s life. He recounts being fascinated as a child by finding a cluster of fossilised whelks on a cliff overhang beneath Skye’s famed Kilt Rock. As a 15-year-old, he unearthed Neolithic arrowheads and pottery while digging peat near his home in Ellishadder.

His keen interest in this field, alongside a rich knowledge of the Trotternish peninsula’s brooding landscapes and coastline, has seen Ross become an integral part of efforts to discover more about Skye’s dinosaur past.

That extensive work was acknowledged by the Palaeontological Association last year when they presented him with the Mary Anning Award, an accolade given to those who, while not formally employed in research, have made an outstanding contribution to palaeontology.

Ross has some fantastic stories about his dinosaur-hunting exploits over the years. In 1997, he recovered the ulna and radius bones belonging to the earliest known thyreophoran dinosaur, similar to a stegosaurus, from Bearreraig Bay.

He was first alerted to the remains by banker Colin Aitken who, while holidaying in the area, had noticed a bone in a rock on the beach. Unable to carry it and his two young children, Aitken hid the rock behind a ruined building. When Ross arrived, however, someone else had got there first.

The rock had been smashed and the bone removed. Left in the rubble, however, were two other bones (the ulna and radius) and Ross was able to safely collect these.

Two decades on, he still laments that the humerus of the same animal was gone before he got there. “I could see the rock that was left had a groove in it which indicated there was quite a substantial limb bone there but we have never been able to trace it,” says Ross.

While incidents of reckless fossil collecting remain thankfully rare, gathering dinosaur specimens is not without its perils, as Clark can testify to after discovering Skye’s second ever set of footprints in 1996.

He gathered a team to help remove the prints from the limestone block at Port Earlish. “We used rock saws, pneumatic drills, heavy chisels and sledgehammers to remove them,” says Clark. “It took us a week to cut about 2-3cm – it was very difficult to cut through the rock.”

Then disaster struck. “I stood up during lunch and my leg broke,” he says. “It snapped through the tibia and fibula. I think what happened is that it got a stress fracture from leaning up against the rock when someone was using a pneumatic drill.

“I was standing there on one leg with the other leg dangling. I shouted over: ‘I’ve just broken my leg’ and everyone laughed at first.”

Once the enormity of the situation became apparent, Clark was airlifted from the beach by helicopter to hospital. His leg had shattered in at least 40 places. It was feared initially that the limb might need to be amputated, but the surgeons managed to painstakingly patch it back together.

It didn’t put him off. Later that same year, Clark returned to Skye – on crutches – to lead a group of geologists. “While I was up there I found a tailbone of a theropod dinosaur,” he smiles.

Another of Clark’s most prized Skye specimens is displayed pride of place in the Hunterian: the world’s smallest dinosaur footprint. Believed to belong to a theropod, the 1.78cm print is similar in size to that of a blackbird and was officially ratified by Guinness World Records in 2006.

He also found the first theropod tooth on Skye at Valtos in 2008. “I deliberately went there to find a tooth,” says Clark. “Someone had found a sauropod tooth and I thought it would be nice if we had one in our museum too. Instead I found a theropod tooth. That was exciting.”

With their adventures in dinosaurs now spanning a quarter of a century, Clark and Ross have forged a firm friendship. According to Clark, there have consistently been new discoveries on Skye almost every year from 1996 to the present day.

Since 2013, Clark, Ross and Brusatte have worked closely together as part of the PalAlba collaboration which comprises palaeontologists, geoscientists and other related experts in this field.

Brusatte secured grant funding from National Geographic to support their work and the group is in the process of making and collating new finds with the aim of publishing these discoveries later this year and into early 2018.

“Middle Jurassic fossils are very rare and Skye gives a unique window into that,” says Brusatte. “The Middle Jurassic was a very interesting time in Earth’s history and the evolution of dinosaurs and other reptiles. This is probably when the first birds were evolving.

“Each fossil is a new clue,” he adds. “It is like working at a crime scene where nobody has found any fingerprints before, or there is only a couple of partial fingerprints. If you find a new one, then it is a big deal and that is the stage we are at in Skye.”

Brusatte is sanguine when asked what the Holy Grail of dinosaur-related discoveries on Skye would be. “A bird,” he says, before quickly adding that such a find would not be without its challenges.

“Birds are small and lightweight with hollow bones. They have fragile skeletons. It is very hard to preserve birds as fossils. But the places where most fossil birds are found, at least from the age of dinosaurs, are lagoons and that is what we have on Skye.

“That is something we very possibly could find some day and that would be a huge deal: the world’s oldest bird, in Scotland. It is the sort of find that would make someone’s career and for all of us, when we are out there, I think that is in the back of our minds now.”

It is a sentiment cheerily echoed by Clark. “Obviously a bird,” he grins, “but I’m going to try to be a little more realistic and say finding the lower or upper jaw, a substantial bit of the skull of a dinosaur, would be very useful and I think that is quite possible.”

The fossils and bones found so far may only be scraping the surface of the dinosaur secrets that this picturesque corner of Scotland could hold. “There is still so much more to be found on Skye,” says Clark. “Every year something turns up – and we will be there waiting for it.”

COMPETITION: Win tickets to Jurassic Kingdom as dinosaurs descend on Glasgow