LOCH NESS: Hundreds of hopeful volunteers joined a two-day hunt for Scotland's fabled Loch Ness monster on Saturday and Sunday, in what organisers described as the biggest search for the elusive "Nessie" in more than 50 years.

The Loch Ness Centre, which partnered with voluntary research team Loch Ness Exploration to organise "The Quest", said they would be using surveying equipment that had not previously been tried at the loch, including thermal drones.

Volunteers from around the world were allocated locations around the 23-mile (37-km) long lake from which to monitor for any signs of Nessie, while others took to boats. A hydrophone was also used to detect acoustic signals under the water.

"We did hear something. We heard four distinctive 'gloops'," said search leader Alan McKenna. "We all got a bit excited, ran to go make sure the recorder was on and it wasn’t plugged in."

The first written record of a monster relates to the Irish monk St Columba, who is said to have banished a "water beast" to the depths of the River Ness in the 6th century.

The most famous picture of Nessie, from 1934, showed a head on a long neck emerging from the water, but 60 years later it was revealed to have been a hoax that used a sea monster model attached to a toy submarine. Countless unsuccessful attempts to track down the monster have been made in the years since.

U.S. volunteer Caroline McNamara's interest in Nessie began when she was at school.

"I chose the Loch Ness monster as my essay assignment, and I thought, 'oh 20 years later it comes full circle so I might as well come and join the hunt' since I heard it was happening," she said, adding that so far they had not found any evidence.

"The waves were really choppy. The rain was really coming down and there were a lot of boats on the water ... they all came up and waved and I’m like, 'this is a bad time, we’re trying to listen for Nessie' but it is what it is."

Nessie enthusiasts who were unable to make the trip were invited to take part by watching live streams from the team's web cams for any mysterious sightings across the waters.