If you only leave the Old Town for one afternoon, make it Leith. This is Edinburgh's best-eating district, a former port on the water about 25 to 30 minutes' walk north of the New Town, and its concentration of good food and drink is unmatched in the city: two Michelin-starred restaurants on the waterfront, a run of serious bars and bakeries, and the Royal Yacht Britannia moored at the docks. Give it half a day for the essentials, or a full day to do it justice.
Leith has always been its own place. It was a working port for centuries and only became part of Edinburgh in 1920, and it still reads as a coastal town rather than a suburb, gentrified in patches but keeping its grit. The Shore, the cobbled quayside where the Water of Leith meets the docks, is the pretty heart of it and the anchor for this guide. Since the tram extension opened in 2023, getting down here is easier than it has ever been.
The honest shape of a Leith day is a slow graze downhill. You start at the top of Leith Walk, work your way down through the bakeries, pubs and cocktail bars of the neighbourhood's middle, land on The Shore for lunch and a drink by the water, then finish at the Britannia or push on to Newhaven harbour. It's a food-and-drink district first, so come hungry and don't expect a dense trail of museums. Here are the eleven spots I'd build the day around, in the order I'd walk them.