Railroading has changed a lot since I took this photo of a massive coal train derailment on the shared BN/CN route through Burnaby, a suburb of Vancouver.
Built over boggy ground, the heavily loaded trains apparently set up oscillations which made the cars unstable, until eventually one would derail, setting up a chain reaction.
The cure was to strengthen the subgrade to eliminate this effect.
Although not exactly welcome at the site, no-one really bothered you if you kept out of the way and didn't do anything foolish. Still, it would not be the sort of picture that the PR department would welcome.