Princes Street is one of the major thoroughfares in central Edinburgh, Scotland, and its main shopping street. It is the southernmost street of Edinburgh's New Town, stretching around 1 mile (1.6 km) from Lothian Road in the west to Leith Street in the east. The street is mostly closed to private cars, with public transport given priority. The street has virtually no buildings on the south side, allowing panoramic views of the Old Town, Edinburgh Castle, and the valley between.
Only the east end of the street is open to all traffic. The bulk of the street is limited to trams, buses and taxis.
Princes Street was originally to have been called St Giles Street after the patron saint of Edinburgh. However, King George III rejected the name, St Giles being also the patron saint of lepers and the name of a notorious 'rookery' of slums in London. The street is named after King George's two eldest sons, the Prince George, Duke of Rothesay (later King George IV) and the Prince Frederick, Duke of York and Albany.
It was laid out according to formal plans for Edinburgh's New Town, now known as the First New Town. These were devised by the architect James Craig and building began around 1770. Princes Street represented a critical part of the plan, being the outer edge, facing Edinburgh Castle and the original city:"Edinburgh Old Town". Originally all buildings had the same format: set back from the street with stairs down to a basement and stairs up to the ground floor with two storeys and an attic above. Of this original format only one such property remains in its original form. Through the 19th century most buildings were redeveloped at a larger scale and the street evolved from residential to mainly retail uses.