In British Columbia, the best sites are located in the old gold rush communities in the Kootenays and south Okanagan. Sandon, located just east of New Denver on hwy 31A is ripe with abandonned mining & railroad equipment, and I noticed the last time I was there that they've got some of Calgarys' original trolley busses there as well. Well worth the visit. Take the trip up to Idaho peak while you're there.
The drive from New Denver to Kaslo is great, there's some abandonned buildings (A train stopover I believe) old rail bridges over creeks, and if you keep an eye on the mountains you'll see lots of old mines, lots of abandonned mining equipment.
The whole Kettle Valley rail system is pretty interesting. The most impressive trestles were destroyed in the KLO fires near Kelowna a few years back, but there are some good ones right around the Castlegar leg of Arrow lake, and there are some neat tunnels on the KVR around trail to Christina Lake.
If you're headed through Grand forks to Kelowna, on the west side of town (headed up the big hill) you'll see what I believe is an abandonned Dhoukabour village. It's on private property & I don't know how to get to it, but if you could figure it out it would be well worth it for taking some pix.
If you want to check out an old hippie commune near Cherryville BC PM me, and I'll give you directions... it's on private property but I know the owners and can make a call so that you won't get shot when they see you wandering around down there