First, let's clear one thing up: the Federation of Bosnia and Herzegovina is one of two regions of the country Bosnia and Herzegovina. (The other is the tongue-twisting Republika Srpska.) The Dinaric Alps, one of the most rugged ranges in Europe, separate it from neighboring Croatia. The splashiest waterfalls—there are hundreds in this region—can be found at Una National Park. Start in the capital of Sarajevo at the Bascarsija, the 15th-century bazaar that’s the cultural heart of the city. Towering above is the elegant Gazi Husrev-beg Mosque, a relative newcomer from the 16th century. Mountain roads take you to medieval villages like Jajce, crowned by a hilltop citadel, and Mostar, where majestic stone bridges span the impossibly blue Neretva River. The town of Stolac is one of the oldest, with ruins dating back to the Romans and even earlier.