The mysteries of Loch Ness are being explored to new depths using the latest in robot technology.

Operation Groundtruth hopes to reveal fresh insights into the 755ft (230m)-deep loch, said to be home to the legendary Loch Ness Monster.

Disappointingly for monster hunters, early findings have revealed claims made earlier this year about a "Nessie trench" in the northern basin of the loch are incorrect.

It is one of many projects undertaken in the huge body of water as scientists and enthusiasts attempt to reveal its secrets.

July 22, 1933 - Modern interest in the monster was sparked by George Spicer and his wife's sighting of "a most extraordinary form of animal" crossing the road in front of their car.

April 19, 1934 - British surgeon Colonel Robert Wilson takes a picture that appeared to show monster rising out of the water of the Loch.

The photo was considered to be the best evidence of the existence of a sea monster in Loch Ness. Wilson refused to have his name associated with the picture and it became known simply as The Surgeon's Photo.

The picture was later debunked as an elaborate hoax using a toy submarine outfitted with a sea-serpent head.

July 13, 1934 - The Sir Edward Mountain expedition. A total of 20 men with binoculars and cameras surveyed the loch every day between 9am and 6pm for five weeks but results were inconclusive.

December 1954 - A fishing boat observed sonar readings of a large object at a depth of 146m. The object was keeping pace with the vessel and was detected travelling for 800m before contact was lost.

April 23, 1960 - Engineer Tim Dinsdale filmed a hump crossing Loch Ness, leaving a powerful wake. He had been hunting for the creature and allegedly spotted the animal on his last day.

He described the object as reddish with a blotch on its side.

May 21, 1977 - Loch Ness Muppet picture taken by Anthony "Doc" Shiels, while camping beside Urquhart Castle. Shiels, a magician and psychic, claimed to have summoned the animal out of the water.

1987 - Operation Deepscan. Some 24 boats equipped with echosounder equipment were deployed across the whole width of the loch. The scientists made sonar contact with a large unidentified object.

After analysing the echosounder images, scientists believed it to be debris at the bottom of the loch.

2003 - A full search of the loch using 600 sonar beams and satellite tracking was undertaken. No animal of any substantial size whatsoever was found and scientists involved in the expedition admitted the Loch Ness monster was a myth.

April 19, 2014 - A satellite image on Apple Maps showed what appeared to be a large creature just below the surface of the water of Loch Ness. It was later claimed to be merely the wake caused by a boat on the loch.

April 13, 2016 - A 30ft-long model of Nessie that sank to the bottom of Loch Ness 50 years ago found by an underwater robot. The prop was built for the 1970s film The Private Life of Sherlock Holmes but was lost at the end of production.