Why go
This orientation helps visitors avoid wasting time crossing the same steep ground repeatedly. The Castle, Royal Mile, Princes Street Gardens and Scottish National Gallery show how the Old Town and New Town meet, while Grassmarket and Cowgate reveal the lower streets. Use those landmarks to decide which side of the gardens to explore before moving on.
The full story
Start with the central shape. Edinburgh Castle stands on its crag at the western end of the Old Town, and the Royal Mile follows the ridge east towards the Palace of Holyroodhouse. Narrow closes fall away from this spine, while Grassmarket and Cowgate occupy lower ground beside it. This is the oldest, densest part of the centre and the most demanding area for level changes. North of the ridge, Princes Street Gardens mark the former Nor' Loch. Beyond them, the New Town was laid out in the late eighteenth century with broad streets and a more regular Georgian plan. The Scottish National Gallery beside the gardens provides a useful point of connection between the two urban forms. The larger landscape remains visible from many central streets. Arthur's Seat rises beyond Holyrood, Castle Rock dominates the western end, and the Firth of Forth lies to the north. Keep a central day focused on one side of the gardens at a time, then cross deliberately when the contrast between Old Town and New Town is the reason for the walk.