It is the southernmost street of Edinburgh's New Town, stretching around 1.2 km from Lothian Road in the west, to Leith Street in the east. The street lies on the line of a medieval country lane known as the Lang Dykes and under the first plan for the New Town was to have been called St Giles Street after the patron saint of Edinburgh.
However, when King George III was shown plans for the proposed New Town by Sir John Pringle, he objected to the name as he associated it with the notorious slum area of St Giles, London. At Sir John’s suggestion, the street was instead named Prince's Street after King George's eldest son, Prince George, later King George IV. By the late 1830s the apostrophe in the name had largely fallen out of use, giving the street its present day name of Princes Street.
It was laid out according to formal plans for Edinburgh's New Town 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, no.95, 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 use, with shops still lining the landmark street today.