This is an easy one. Alaska State Ferry system from Bellingham, WA to Juneau, followed by a stay in Juneau and flight home to Seattle. I’d done it solo many many years ago, and 'twas magical. A few years ago with the spouse, not so much. (Serves me right trying to re-create something special in exactly the same way; that NEVER EVER works for anything.)
The trip took place during a record-breaking heat wave, and on the ferry the heating system broke. In the “On” position. This happened when we were napping in our “stateroom,” and we woke up from heavy naps literally thinking the boat was on fire. It was more than 100 degrees in the room, heat blasting away. This continued for about 18 hours after that; the room was completely unusable for that length of time, and barely bearable after that. The crew were complete jerks about it; I say this as a government employee myself, but they exhibited the finest not-giving-any-shits attitude of any public servant that I’ve ever seen. Not even a hint of sorry-for-your-inconvenience; it was like being roasted by the IRS.
Once in Juneau, we “upgraded” to a lovely room on an upper floor of our lovely hotel. The record-breaking heat proceeded to follow us from the south (and from the boat, I guess), and the room was in the 90s. No AC, of course, because who needs it in Alaska? A lower floor with no view would have been far better, but by that time there was none available.
We tried to cut the trip short. I’d bought first class tickets to Seattle, but I stupidly assumed that meant changing the flights was possible without extremely stiff penalties. Not so! We stayed.
On the flight home, the plane sat on the tarmac in Juneau for about an hour and a half, with (guess what!) no AC. Also, they would not serve us drinks during the wait. I got my beer when the plane finally took off for its very short flight, the flight attendant saying “Better chug it!” Get bent, ma’am.
We always say, when you go on a trip, you create memories. They aren’t necessarily good memories, but they’re memories! But there was one good one. We went out to Mendenhall Glacier, and the breeze happened to be coming right across the ice (even though it was a mile or more away). That breeze was about 60 degrees Fahrenheit, in the middle of the inescapable heat everywhere else. It was easily one of the loveliest moments of my entire life.