When I was hunting in the Selous Game Refuge in Tanzania, back in 1972, the Chinese were building a railroad there as well. We used to drive past their work parties almost every day. Interestingly they were using concrete cross ties (sleepers), something I had never seen before.

After the reunification of Germany, the East German rail lines had to be rebuilt because they were using concrete cross ties made with sand dredged from the North Sea, and the salt content was rusting out the reinforcing rods, or so my former brother-in-law, who was high up in the Bundesbahn at the time, told me.