Refugees line up to apply for asylum at a reception center in Berlin, Germany. Figures released last week showed that about 180,000 asylum applications were filed in the first six months of 2015, more than twice as many as in the same period last year. Markus Schreiber/AP hide caption

itoggle caption Markus Schreiber/AP

Berlin's Humboldt University — named for its founder, the 19th century philosopher and linguist Wilhelm von Humboldt, and his brother, naturalist Alexander von Humboldt, pictured here — is one of several German universities attracting U.S. students. More than 4,000 Americans are studying in German universities. Markus Schreiber/AP hide caption

itoggle caption Markus Schreiber/AP

Berlin's Humboldt University — named for its founder, the 19th century philosopher and linguist Wilhelm von Humboldt, and his brother, naturalist Alexander von Humboldt, pictured here — is one of several German universities attracting U.S. students. More than 4,000 Americans are studying in German universities. Markus Schreiber/AP hide caption

itoggle caption Markus Schreiber/AP

Marchers carried a multicolor flag during Warsaw's annual gay pride parade earlier this month. Poland prohibits gay marriage but activists say attitudes toward gays have improved in recent years. Alik Keplicz/AP hide caption

itoggle caption Alik Keplicz/AP

Unmanned observation towers, funded by the European Union, have sprouted recently along Poland's border with Russia. This one is located outside the sleepy Polish border village of Parkoszewo. Soraya Sarhaddi Nelson/NPR hide caption

itoggle caption Soraya Sarhaddi Nelson/NPR

A group of Afghan women are attempting to reach the 24,580-foot summit this summer. In mid-May, two of the climbers, along with two American chaperones, visited Afghanistan's highest mountain to see the terrain firsthand in preparation for the historic climb. Soraya Sarhaddi-Nelson/NPR hide caption

itoggle caption Soraya Sarhaddi-Nelson/NPR