It's sandwiched between mountains and the Adriatic Sea, and for me there was a lot of hiking up and down winding, sloping streets and a lot of relaxing by the sea.
Dan's conference was at a Physics Centre that was about 8km north of the city, so buses were ridden daily in to town to explore. But right by the Centre was probably Trieste's main attraction: Miramare Castle, so I spent the first day touring that and wandering around the expansive gardens, generally trying to avoid the Italian sun.
Another notable spot near Trieste is the Grotta Gigante, or Giant Cave. It's a bit further up in the mountains but has been declared the largest tourist cave in the world, and I think it probably is. The thing is huge! And has a lot of steps (about 1000) to get down and back up.
Cave photos are generally bad, and ours really aren't an exception, so I'll just submit you to two.
The first gives you some idea of the size, and the second for the stairs in the background you can just see zig-zagging their way down. So. Many. Steps. The two white vertical things have very thin wires inside them and I think have to do with measuring seismic variations. Or possibly tides. Our guide spoke a very sort of mumbled hurried English after the spiel in Italian.
Trieste itself was interesting. It has a lot of Roman ruins, and you can see the influence of Vienna (or so I'm told) in the architecture.
All three buildings are from the main square downtown, the Piazza Unita d'Italia. I took a ton of photos of the mosaic work on the last building. It looks really Pre-Raphaelite-ish to me, but I'm not sure that was intentional.
And that'd be Dan next to a Roman arch, and the ruins of a Roman theater.
The same day we explored downtown we spent some time sitting on a pier in the harbor, getting our obligatory feet-in-large-bodies-of-water-across-the-world photo and getting a bit of sun.
The water was actually quite a bit below the level we were sitting on, so this is us practically falling into the water trying to get our feet wet.
It was a bit windy.
And then a giant wave came and I got soaked up to my knees.
It was a good week spent in a place I never thought I'd go. So thanks theoretical physics for having conferences in random spots around the globe.