Tales of monsters in the loch date back to before the times of Princess Katharine, who shared the stories with the hatchlings on Avalon. In the 6th century, St. Columba traveled to Loch Ness, where he tamed one of the animals living there.
In 1994, David Xanatos commissioned Dr. Anton Sevarius to capture the Loch Ness monster. He and his security force, led by Bruno, captured one of the beasts, dubbed Nessie, and were pursuing one Sevarius called Big Daddy, when the Avalon travelers appeared on Loch Ness. During the pursuit of Big Daddy, the security team overturned the skiff carrying the travelers, and they captured Angela, bringing her to a secret base.
Goliath, Elisa, and Bronx washed up on the shores of Loch Ness, where they continued the search for Angela. During the day, Elisa found members of Xanatos' Security force, whom she tracked back to their base. Meanwhile, Sevarius had collared Nessie, and set her free, so as to track her to Big Daddy.
Unfortunately for Sevarius, the Avalon travelers managed to rescue Angela, un-collar Nessie, and destroy Sevarius' submarines.
According to a tour guide, the loch is 24 miles long, a mile and a half wide, and up to 900 feet deep.