At the Teufelsberg, or Devil's Mountain, a similar listening post -- this one an abandoned U.S. radar station and observation tower -- has been taken over by Berlin's ubiquitous graffiti artists.

A silent tour around the strange, white radomes -- weatherproof microwave antennae cases reminiscent of Disney's Epcot Center -- gives an eerie feeling in the age of the recent NSA disclosures from Edward Snowden.

Once a secretive military enclave, the full history of the complex won't be revealed until documents are declassified in 2022, but it's estimated more than 1,000 spies worked here throughout the Cold War, 24 hours a day, 365 days a year, as part of a surveillance network known as ECHELON.

For me, though, nothing captures the Cold War spy's world better than the hot and stuffy Stasi Museum, where the GDR spymaster's suite of offices and conference rooms have been preserved unchanged.

In these spartan chambers, banks of Bakelite telephones, steel desks and chunky typewriters evoke what renowned Nazi trial chronicler Hannah Arendt might have called "the bureaucracy of evil," had she written about East Germany rather than the Third Reich.

As the milky light reflects off the wood paneling, a shudder runs down my spine.