Mostar is named after its bridge keepers, the mostari who guarded the Old Bridge in Ottoman times, so the city has never really been about anything else. The bridge went up between 1557 and 1566, stood for more than four centuries, and was shelled into the Neretva on 9 November 1993. It was rebuilt stone by stone and reopened in 2004, and since 2005 it has been on the UNESCO World Heritage list.
That story is the reason to come, but it isn't the whole city. The old town is small and steep, a few lanes of copper shops and coffee houses. Walk ten minutes away and you reach the former front line, where shot-up buildings stand beside new ones. Mostar is also the best base for the south: the cliff-side tekke at Blagaj, the walled hill town of Počitelj and the Kravica waterfalls are all within an hour.
Three days is the right length. The bridge deserves a morning and a dusk, the other half of the city only makes sense on day two, and day three is a long day trip. Start on a Tuesday, which keeps the mosques off Friday prayers. More on the country at Bosnia and Herzegovina. Mostar sits neatly between Sarajevo and Dubrovnik.