Tourists from Holland peak through a crack in a still-existing portion of the Berlin Wall at the main memorial to the Wall in Bernauer Strasse on the 22nd anniversary of the fall of the Wall on November 9, 2011 in Berlin, Germany. The Berlin Wall, erected by the communist authorities of then East Germany in 1961, divided the city and prevented East Germans from travelling west until the collapse of the Eastern Bloc in 1989. (Photo by Sean Gallup/Getty Images)

An African migrant stranded in Costa Rica bathes at a makeshift camp at the border between Costa Rica and Nicaragua, in Penas Blancas, Costa Rica, July 14, 2016. Thousands of African migrants are currently stranded in Costa Rica after they were denied entry into neighbouring Nicaragua, which they have been using as a crossing point in order to reach the United States. According to the Costa Rican Red Cross, most of these people from Africa, Asia and Haiti. It has been reported that many of them paid smugglers to reach Central America. However, when they arrived at the border gates, they were denied entry and were left with nowhere to go. (Photo by Juan Carlos Ulate/Reuters)

A woman carrying a bundle on her head wait in line to cross the border into Colombia through the Simon Bolivar bridge in San Antonio del Tachira, Venezuela, Sunday, July 17, 2016. Tens of thousands of Venezuelans crossed the border into Colombia on Sunday to hunt for food and medicine that are in short supply at home. It's the second weekend in a row that Venezuela’s government has opened the long-closed border connecting Venezuela to Colombia. (Photo by Ariana Cubillos/AP Photo)

Men help remove messages and prayers written by thousands of people addressed to God from the cracks in the Western Wall in preparation for the up coming Jewish Passover holiday on March 28, 2012 in Jerusalem's old city, Israel. All the notes once collected will be buried in a special place at the Mount of Olives.according tro Jewish law. Passover begins in the evening of Friday, April 6 and commemorates the story of the Exodus where the ancient Israelites were freed from slavery in Egypt. (Photo by Uriel Sinai/Getty Images)

Climbers ascend the walls of the Westway Climbing Centre on June 15, 2011 in London, England. The Westway indoor climbing centre is located under the A40 flyover in Shepherd's Bush has over 350 climbing routes, some of which rise to over 14 meters. (Photo by Oli Scarff/Getty Images)

A protester wears a pig mask as he marches through the streets of downtown Vancouver with thousands of people participating in the Occupy Vancouver protest on October 15, 2011 in Vancouver, British Columbia, Canada. Thousands of people are taking to the streets in cities across the world today in demonstrations inspired by the Occupy Wall Street protest in New York City. An estimated 2,000 people participated in the Vancouver occupation. (Photo by Jeff Vinnick/Getty Images)

A plume of smoke rises above Gaza City as Israeli air strikes hit on August 18, 2011 in Gaza City, Gaza. The airstrikes came hours after attacks by militants killing Israelis in a cross border operation near Eilat, Southern Israel. (Photo by Christopher Furlong/Getty Images)

An Israeli missile is launched from the Iron Dome missile system in response to a rocket launch from the nearby Palestinian Gaza Strip, on March 12, 2012 near Ashdod, Israel. (Photo by Uriel Sinai/Getty Images)