If like me you grew up reading Le Carré and Len Deighton then, like me, you should check out the former HQ of East Germany’s Ministry for State Security, better known as the Stasi. It’s at 103 Ruschestrasse, a 15-minute U-Bahn ride from Alexanderplatz (get off at Magdalenenstrasse on line U5). It’s now a museum―left just as it was when the Wall came down. A suite of heavily panelled rooms―all sturdy Sixties furniture and Bakelite phones―was where the Stasis’s last leader Erich Mielke and his cronies controlled hundreds of thousands of secret police and informants who in turn controlled the population of the GDR through fear and disappearance. It’s completely atmospheric; and very creepy. Also on view every type of covert spy camera hidden in briefcases, belts, ties, shoes, pens, cigarette packs and an AK-47 concealed in a suitcase. It looks quaintly amateurish now but these guys were the ‘shield and sword of the party’ and they killed non-believers. www.stasimuseum.de