Researchers and enthusiasts on Saturday began searching for the Loch Ness Monster in Scotland.

The expedition has been billed as the largest search for the monster, nicknamed "Nessie," in five decades.

What do we know about the search for Nessie?

Drones with thermal scanners, boats with infrared cameras and an underwater hydrophone are being deployed in the search.

The scanners allow researchers to find anomalies in the depths of the lake and the hydrophone could identify underwater calls.

Dozens of volunteers from around the world are participating in the search at 17 observation points around the lake.

"It's always been our goal to record, study and analyze all manner of natural behavior and phenomena that may be more challenging to explain," said Loch Ness Exploration co-organizer Alan McKenna.

"The weekend gives an opportunity to search the waters in a way that has never been done before, and we can't wait to see what we find," Loch Ness Center manager Paul Nixon said.

What is the Loch Ness Monster?

Loch Ness, which lies in the Scottish Highlands, is the United Kingdom's largest lake by volume, at 23 miles (36 kilometers) long and with a maximum depth of 788 feet (240 meters).

Legends around a monster in the body of water emerged as early as 565 AD, when the Irish monk Saint Columba wrote an account of the creature attacking a swimmer.

In 1934, the UK's Daily Mail published a photo that purported to show the Loch Ness Monster. It was later revealed to be a hoax, but helped popularize the image of the creature internationally.

The Loch Ness Center in the Highland village of Drumnadrochit says that there have been 1,100 officially recorded sightings of the monster.

This weekend's search is not the first time researchers have combed the lake for signs of the Loch Ness Monster. In 2018, a DNA survey conducted by a group of researchers found no evidence of any large animals in Loch Ness, only detecting the presence of numerous eels.

sdi/ab (AFP, dpa)