EDINBURGH, Scotland » If you are fortunate enough to travel to the British Isles for a week, do as I say, not as I did.

Scotland for a week in late December — with a quick trip down to London — was a revelation: sparkly, festive, not that cold, endlessly interesting.

It was also punctuated by more than a few dumb decisions, which, in the interest of consumer reporting, I thought I’d share with you.

So many travel stories are written by experts who did everything right — which is why they are travel writers. This article is written out of ignorance, which was bliss until the flight home, when I had time to reflect on what I did wrong and what I’ll do differently next time.

For there will be a next time: There’s much more to explore in Edinburgh’s "seven hills," a city with a history as deeply layered as the rocks it sits upon.

DO stay at the Caledonian (officially called, the Waldorf Astoria Caledonian), if your budget permits it, on your first trip to Edinburgh. It is a five-star hotel at the center of everything, with killer views of Edinburgh Castle. I booked a few months in advance and scored a deluxe room with that glorious view for $250 a night, which is a great deal. Next time, you can be more adventurous — there’s the Hotel Missoni, owned by the Italian fashion house, or any number of good bed-and-breakfast places — but it’s smart to plant yourself in central Edinburgh on an initial visit.

DON’T decide at the last minute to book a room at the Caledonian for the night before you arrive. It’s always nice to go from the airport straight to the hotel if you arrive at breakfast time — when many overseas flights do arrive — but there’s a 3 p.m. check-in. Some (many?) brave souls kill time walking around museums or park benches, but not me.

I had known early on that my United Airlines flight from Pittsburgh — with a layover in Newark, N.J. — arrived at 7:30 a.m. But it didn’t occur to me until the day before I left that I would really need to get in the room early to sleep. That one night cost me $575.84. I hesitated: Maybe I could camp out in the lobby of the airport Hilton instead? I decided to spring for it, but honestly, dumb, dumb, dumb.

DO go to Scotland in the winter. There are few tourists, no crowds, and while it was cold in the north and in the Orkneys, it was in the 40s in Edinburgh when I was there. The weather was so changeable and romantic, full of the mists, watery skies and wind-swept, sunlit clouds, right out of a J.M.W. Turner painting. It is windy there, so much so that umbrellas are somewhat useless. If you get really cold, buy one of those Harris tweed "cowl" scarfs that you wrap around your neck and button at the ends. It really keeps out the wind. Everything, it seems, is made from Harris tweed there: iPad cases, coasters, pencil cases, sleep masks.

DON’T buy a kilt, which are priced at 400 pounds ($700) or more in some stores on the Royal Mile, in Edinburgh’s Old Town, in the shadow of Edinburgh castle. Don’t be tempted to buy the cheap ones in the souvenir shops, either, which are essentially polyester printed with tartan. I found a wonderful vintage wool kilt/skirt that fit perfectly for $39 at a secondhand store called The Ragged Hem. Or go to a "kilt hire" shop where you can rent them.

DO have dinner at The Witchery. It’s something of a tourist trap, a deliberately theatrical restaurant, all old oak paneling (salvaged from a cathedral), tapestries, silver candelabras and tartans — think Macbeth crossed with Walter Scott — but the building dates from the 1500s and there is a plaque out front that claims Samuel Johnson, the 18th-century essayist, and his faithful biographer James Boswell supped there. My daughter and I had dinner there on Christmas Eve. The food was somewhat retro — I had to explain to my daughter that yes, steak tartare is raw but really delicious — and suitably opulent although not outrageously expensive. Then we walked back to the hotel through the cobblestone streets under Edinburgh Castle, which was flooded with a lurid red light. The red was for the poppies that were everywhere, marking the 100th anniversary of World War I and the sacrifices made by British — and Scottish — soldiers.

DON’T bother to have lunch at The Elephant Room on George IV Bridge Street unless you are a huge Harry Potter fan. For yes, this is the pub where J.K. Rowling came every day, a penniless single mother, to write her book. The food isn’t particularly good, but it’s a bright, cheerful space and it’s just around the corner from the National Museum of Scotland, which includes among its artifacts the stuffed body of Dolly the sheep, the first successful clone of a mammal from an adult cell.

DO stop in at the National Gallery of Scotland on Edinburgh’s The Mound, which must be one of the most charming museums anywhere. It’s a squat neoclassic building that doesn’t charge admission, although it gladly takes donations. Inside, there is an surprisingly impressive collection of paintings — Van Dyck, El Greco, Cezanne, Monet, Sargent, Constable — in charming red rooms that belong in a painting themselves.

DON’T plan to travel the day after Christmas, which is Boxing Day in the U.K., when virtually no trains are running. It’s a tradition, because Boxing Day — the day when, in days past, servants and tradespeople received gifts in "Christmas boxes" — is supposed to be a holiday. Actually, it has morphed into something closer to a Black Friday. When I arrived in London by air, the area around Trafalgar Square was jammed with bargain hunters, who must have driven into town because not even the London Underground was running.

DO go to church, even if you don’t go to church — or, as they say in the Scots language, "kirk." We went, on Christmas Day, to St. Giles Cathedral in Edinburgh, founded in the 12th century, considered the cradle of Presbyterianism. The great Protestant reformer John Knox is buried under a parking lot (Space 23) that was once a cemetery. Seems disrespectful at best, but there’s a statue of him inside the cathedral. (A statue of Adam Smith, author of "The Wealth of Nations," stands just outside.)

DO go to or from London by express train, if you have time. It’s four hours and 45 minutes, and the views are beautiful, especially in the Scottish border country outside Edinburgh. Once you arrive in London, have a martini at the bar at Dukes Hotel on St. James Place. Ian Flem­ing, author of the James Bond spy novels, reportedly concocted the famous "shaken, not stirred" vesper martini there. It is very strong and very dry, so if you want something more girlie, try the whiskey sour, which is outstanding.

DON’T buy a bottle of whiskey on the Royal Mile in Edinburgh, at least if you’re planning to travel by plane to London. An 8-year-old bottle of Old Pulteney was $75.03, and when your correspondent discovered no trains running on Boxing Day, she flew instead — for less money than the train — but had to pay an extra $60 to put the bottle of scotch in checked luggage. That bottle of scotch is going to last a long, long time.

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