Luxembourg is one of the smallest city-states in Europe. The rivers Alzette and Pétrusse, which meet here, cut through the city. It's a tiny place, and divides into three distinct sections. The Old Town, on the northern side of the Pétrusse valley, is not clearly ancient, but is very appealing and its tight grid of streets holds most of the city's sights. On the opposite side of the Pétrusse is the Modern City which is less attractive and of interest only for its train station.
The Old Town focuses on two squares; the more important one is Place d'Armes, packed with cafés and restaurants. To the north lie the city's principal shops, mainly along Grande Rue, while on the southern side a small alley cuts through to the larger place Guillaume, the venue of Luxembourg's main general market.
The city occupies an ideal defensive position and its defenses were reinforced on many occasions, hence the massive bastions and subterranean artillery galleries of today.