THE ONE CASTLE
At the top of the processionary route through the Old Town known as the Royal Mile, Edinburgh Castle sits on an easily-defended rocky outcrop. Hence the Scottish Royals decided to make it their home in the 11th century. Inside, the Romanesque St Margaret's Chapel is the oldest building in the city, the Royal Apartments are open for envious gawking and the Honours of Scotland – the Scottish equivalent of the Crown Jewels – are on display. See edinburghcastle.scot
THE ONE DRINK
A short amble down the Royal Mile brings you to the Scotch Whisky Experience, which celebrates Scotland's globe-conquering spirit of choice. It's home to the world's largest scotch whisky collection, some of which you can sample on tasting tours. But the main exhibitions do a good job on whisky's origins, making and cultural impact, with plenty of interactivity. See scotchwhiskyexperience.co.uk
THE ONE TOUR
Real Mary King's Close is one of several alleyways off the Royal Mile, many of which have been covered over to the point where they're subterranean. This one has been opened to visitors, many of whom have signed up to the tour for the ghost stories. Far more fascinating, however, are the tales of disease and grim living conditions faced by the 16th- and 17th-century inhabitants. See realmarykingsclose.com
THE ONE HILL
Calton Hill at the eastern edge of the New Town has tremendous 360-degree views over the city and the Firth of Forth, but the real reason to puff and pant your way to the top is the collection of somewhat absurd classical Greek-style monuments. Many of them are half-finished but they led to Edinburgh getting its someone incongruous "Athens of the North" nickname.
THE ONE WALK
In the New Town, between the grand near-uniform Georgian terraces, is a deliciously tranquil gully through which run the Water of Leith. The walking track along it passes the odd folly, and heads towards the Dean Village, once a milling settlement and now home to some of the city's most photogenic housing. It feels like dipping into a country hamlet.
THE ONE YACHT
Edinburgh's port, Leith, plays home to the Royal Yacht Britannia. For 43 years, it transported Queen Elizabeth II and her family around the world, clocking up a whopping 696 foreign visits. It's now open to visitors as a museum, and while discovering how the yacht was run is mildly interesting, the really fascinating aspect is learning about the Queen's surprisingly simple tastes. Opulence is conspicuous by its absence. See royalyachtbritannia.co.uk
THE ONE COMEDY CLUB
Edinburgh becomes the world comedy capital during the Fringe festival in August, but there are plenty of laughs to be had for the rest of the year, too. The Stand has a reputation as the sort of comedy club performers love – crowds tend to be knowledgeable, appreciative and open-minded. Given that a disproportionate number of comics live in Edinburgh, this makes for consistently high-quality line-ups. See thestand.co.uk
THE ONE MEAL
Chef Tom Kitchin, who regularly appears on TV cookery show judging panels, was just 29 years old when he received his first Michelin star – the youngest person to have one at the time. His Leith restaurant – the Kitchin – puts French twists on its dishes, but the aim is to show off the finest in Scottish cuisine. That means Orkney scallops, Highland venison, North Sea halibut and Perthshire pear are in the mix. See thekitchin.com
THE ONE HOTEL
Le Monde goes for an internationalist crowd by decorating each room around a different city around the world. One might be covered in photos of Hollywood stars and the next might be full of arty black-and-white shots of Paris landmarks. Doubles cost from £112. See lemondehotel.co.uk
ONE MORE THING
During its August festival season, accommodation prices in Edinburgh ramp up to wince-inducing levels. Mercifully, this is outside of the university year, so much of the city's student accommodation is available for those smart enough to snap it up early. University Rooms is a good place to go hunting. See universityrooms.com
David Whitley was a guest of Visit Scotland.