See the nests?
You won't if you're looking in the trees. These holes in the sandy soil of Deliblato Sands are sand martin nests. Sand martins are members of the swallow family. Deliblato Sands (Deliblatska Peščara) make up the largest sandy terrain in Europe, and were once part of a vast prehistoric desert. Part of the Sands is only about an hour out of Belgrade.
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