U.S. Marines and sailors arrived in Iceland last week to participate in the largest NATO military exercise since the Cold War. According to local reports, the thirsty soldiers marked their arrival by drinking almost every bar in capital Reykjavík dry.

Some restaurants and downtown bars, like Sæta Svínið and the American Bar, completely ran out of beer supplies, while others were able to make emergency beer runs and borrow from other better-stocked establishments.

It is estimated that between 6,000 and 7,000 U.S. service personnel were present in Reykjavík over the five day period. They are said to have preferred local beers over foreign imports, and sampled everything from craft brews to larger-production lagers.

Local blogger Eiríkur Jónsson spoke to those on the front line, with restaurant and bar workers telling him they had never experienced anything like it. One brewery, Ölgerð Egils Skallagrímssonar, worked overtime to ensure bars received the much-needed supplies, but “they were fighting an overwhelming force,” Eiríkur says.