A preserved rural steam railway!
I love the sight, smells and general ambience of them. A reminder of the gentler times, especially rural ones. My favourite TV programmes are Heartbeat and Herriot's All Creatures Great and Small (original series), which often feature the Yorkshire countryside and sometimes the rural steam railways.
We've managed to find a few holiday cottages to stay in which are at old railway stations, or carriages next to a railway, or the latest was a converted engine shed alongside a preserved steam railway line.