Fish for sale in the fish market in Fraserburgh, Scotland. Ari Shapiro/NPR hide caption

itoggle caption Ari Shapiro/NPR

Teams of volunteer archaeologists travel to Vindolanda during each excavation season. They painstakingly scrape and brush away at the soil to see what they can find. Rich Preston/NPR hide caption

itoggle caption Rich Preston/NPR

A campaign poster in Dublin encourages voters to say no to same-sex marriage ahead of a referendum in Dublin on Friday. Paul Faith/AFP/Getty Images hide caption

itoggle caption Paul Faith/AFP/Getty Images

A man walks out of a polling station in St. Leonard's Church on Thursday in Loftus, England. Ian Forsyth/Getty Images hide caption

itoggle caption Ian Forsyth/Getty Images

Far more than other Western democracies, Britain concentrates its money, power and culture in the capital, London. Elwin van Eede/Flickr hide caption

itoggle caption Elwin van Eede/Flickr

Much of the Netherlands is below sea level, including Amsterdam. Urgenda argues that any rise in the sea level could have a huge impact on the country. Ari Shapiro/NPR hide caption

itoggle caption Ari Shapiro/NPR

Nicola Sturgeon, Scotland's first minister and leader of the Scottish National Party (SNP), delivers a speech in Glasgow, Scotland, on March 28. After its loss at the polls last year on the issue of Scottish independence, the party has quadrupled its membership and is on the ascendant. Russell Cheyne/Reuters/Landov hide caption

itoggle caption Russell Cheyne/Reuters/Landov