The backbone of Prague is the Vltava River (also sometimes known by its German name, Moldau), which runs from south to north with a single sharp turn to the east. The city was originally composed of five independent towns that today represents the historic district: Hradcany (Castle Area), Malá Strana (Lesser Quarter), Staré Mesto (Old Town), Nové Mesto (New Town), and Josefov (Jewish Quarter).
Hradcany, the seat of Czech royalty for hundreds of years, centers around the Prazský hrad (Prague Castle). A cluster of white buildings yoked around the pointed steeples of a chapel, the Prague Castle overlooks the city from a hilltop west of the Vltava River. Steps lead down from Hradcany to the Lesser Quarter, an area dense with ornate mansions built for the 17th- and 18th-century nobility.
Karluv most (Charles Bridge) connects the Lesser Quarter with the Old Town, which is hemmed in by the curving Vltava River and three large commercial avenues: Revolucní to the east, Na príkope to the southeast, and Národní trída to the south. A few blocks east of the bridge is the district's focal point Staromestské námestí (Old Town Square), a former medieval marketplace laced with pastel-color baroque houses. To the north of Old Town Square, the diminutive Jewish Quarter fans out around a wide avenue called Parízská.
Beyond the former walls of the Old Town, the New Town fills in the south and east. The name "new" is a misnomer -- New Town was laid out in the 14th century. (It's only new when compared to the neighboring Old Town.) Today this mostly commercial district includes the city's largest squares, Karlovo námestí (Charles Square) and Václavské námestí (Wenceslas Square). Roughly 1 km ( 1/2 mi) south of Karlovo námestí, along the Vltava, is the ancient castle of Vysehrad high above the river.