Alex Lussi of Swiss mushroom producer Gotthard-Pilze picks a shiitake mushroom inside a former ammunition bunker of the Swiss Army near the town of Erstfeld, Switzerland August 29, 2015. In eleven former bunkers Gotthard-Pilze produces some 24 tons of shiitake mushrooms per year. With the threat of foreign invasion a thing of the past, thousands of military bunkers and fortresses in Switzerland have been put to commercial use, from hotels to data centres, museums to cheese factories. The Swiss army has sold most of these decommissioned strongholds, but about a thousand unused bunkers remain, many still disguised as houses and barns. REUTERS/Arnd Wiegmann PICTURE 19 OF 27 - SEARCH "SWISS BUNKER" FOR ALL IMAGES