Lake Van is the largest lake in Turkey and the second largest lake in the Middle East. It also hides a mysterious ancient castle beneath its depths.

Divers recently discovered the 3,000-year-old fortress during underwater excavations. It is believed that the unique discovery is a remnant of the ancient Iron Age Urartu civilization, also commonly known as the Kingdom of Van.

"There was a rumor that there might be something under the water but most archaeologists and museum officials told us that we won't find anything," the head of the diving team Tahsin Ceylan told Daily Sabah earlier this month.

Some of the walls around the structure reach heights ranging from 3 to 4 meters. Archaeologists also suspect more may be buried beneath the surface.

"We will have to hold underwater excavations to find out about that" Ceylan said.

The researchers who discovered the castle hails from the Van Yüzüncü Yıl University and have been combing the lake for about a decade, according to Hurriyet Daily News.

Last year, the divers discovered a 2.4 square meter area covered in bizarre stalagmites, which they nicknamed the "underwater fairy chimneys", according to The Independent.

“Many civilizations and people had settled around Lake Van. They named the lake the 'upper sea' and believed it had many mysterious things. With this belief in mind, we are working to reveal the lake’s ‘secrets,’” Ceylan said.

"We have shared all these findings with the world. Archaeologists will come here to examine the castle’s history and provide information on it," he said.

Another academic who helped discover the castle explained that the lake waters were once much lower than they are today, allowing villages and the castle to be built in an area now submerged by water.

"As the lake waters rose, people withdrew but the structures stayed there. Even though most of them are in ruins, they are still there. We need to protect these structures first. Other castles in the country have been damaged, but the lake has hidden the castle here and preserved it," Mustafa Akkuş said.