Down a side street off the busy commercial hub of Potsdamer Platz is this relic of the Berlin Wall and the Cold War,an East German watchtower. The “panorama observation tower” originally stood between the Brandenburg Gate and Leipziger Platz and served as a base for border guards. Construction of these crenelated type BT 6 watchtowers began in 1966 and there were at one time 200 of them.

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