Many years ago, me and a friend cycled across Siberia. Cycled in the broadest sense, that is, because back then there wasn't a road all the way across and there was a significant section where we had to push our bikes along the Trans-Siberian. Which was as expected, and fine, except that we soon discovered that we had to walk along the bit where the toilets discharged.
Cue shouts of "Mind the crap".