The Royal Mile (Scottish Gaelic: Am Mìle Rìoghail; Scots: Ryal Mile) is a succession of streets forming the main thoroughfare of the Old Town of the city of Edinburgh in Scotland. The term was first used descriptively in W. M. Gilbert's Edinburgh in the Nineteenth Century (1901), describing the city "with its Castle and Palace and the royal mile between", and was further popularised as the title of a guidebook by R. T. Skinner published in 1920, "The Royal Mile (Edinburgh) Castle to Holyrood(house)".

The Royal Mile runs between two significant locations in the royal history of Scotland: Edinburgh Castle and the Palace of Holyroodhouse. The name derives from it being the traditional processional route of monarchs, with a total length of approximately one Scottish mile, an obsolete unit equal to 1.8072576 km. The streets which make up the Royal Mile are (west to east) Castlehill, the Lawnmarket, the High Street, the Canongate and Abbey Strand. The Royal Mile is the busiest tourist street in the Old Town, rivalled only by Princes Street in the New Town.