"Video shows the remains of an ancient fortress sitting hidden beneath" lake in Turkey

NatGeo:

From the surface, Turkey's Lake Van looks like any other large body of water. Turkey's largest, the lake sits in the far eastern region of the country, near Iran. The lake has a striking blue color and is a tourist attraction, benefiting towns around its rim. But below the surface lurks another town, which had hardly been seen in thousands of years.

During a recent dive to explore the lake, archaeologists from Van Yüzüncü Yil University and a team of independent divers found an underwater fortress.

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the team estimates the remains are roughly 3,000 years old

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The archaeologists believe rising lake levels slowly submerged parts of the city over time