Which Country’s authorities evacuated around 20,000 people from their homes in the western city of Cologne on 27 May 2015 after a World War II bomb was unearthed during construction work?: Germany
Explanation: Seventy years after the end of fighting, parts of Germany remain riddled with unexploded bombs from the Allied campaigns, and construction workers regularly stumble upon them. The unexploded US-made device, which lay five metres underground was set to be defused later in the day, and river traffic on the nearby Rhine was to be halted during the operation with evacuation of 20,000 people from the area. Hundreds of police, firefighters and other helpers were involved in clearing the site for the city's largest evacuation since the end of the war.