9The Drina River House (Serbia)
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Built in 1968 by a group of friends who wanted a place to relax and enjoy nature, the house is both a feat of engineering and a symbol of solitude. It has been rebuilt several times after being swept away by strong river currents, but each time, it stands tall again.
Why it’s lonely: Isolated by water on all sides, with the nearest sign of civilization far away on the banks of the river.