Central Edinburgh has two distinct parts, divided by Princes Street, which runs roughly east-west under the shadow of Castle Rock.
The Old Town, although only about a mile long and 300 yards wide, represents the total extent of the twin burghs of Edinburgh and Canongate for the first 650 years of their existence, and its general appearance and character remain indubitably medieval with its tortuous alleys and tightly packed closes. Containing as it does the majority of the city's most famous tourist sights - including the Castle and the Royal Mile - it makes by far the best starting point for your explorations.
To the north of Princes Street, the New Town, itself well over 200 years old, stands in total contrast to the Old: the layout is symmetrical, the streets are broad and straight, and most of the buildings are Neoclassical in design. Originally intended to be residential, today the New Town is the bustling hub of the city's professional, commercial and business life, dominated by shops, banks and offices.