Divided by the majestic Danube, the city of Budapest is one of the great river-cruise destinations - the first or final call on a tour of some of Europe's most historic cities. Indeed, few rivers take in riches like the Danube. The Hungarian capital, which comprises the once-divided regions of Buda to the west and Pest to the east, remains a dual city defined by its great waterway - many of its most famous sites lined up alongside it. Passengers on Emerald Waterways, when moored opposite the neo-Gothic turrets and arches of the Hungarian Parliament have the elevated Bud Palace, once home to the kings of the Ottoman and Habsburg dynasties, and the beautiful, lush green Margaret Island already in view. It's a city worth getting up early and staying out late for: deciding between its cafés, bars and architectural delights, while learning of its fascinating past, is a difficult but not impossible task - here's how you could do it!