The Bamboo Railroad. They were powered by tiny motors and a rubber belt. To speed up, one simply moved the motor further from the axle, thus tightening the rubber belt. If someone showed up going the other direction, we would jump off, disassemble the platform, let them pass, reassemble, and jumpstart the motor again.
I hope this recording speaks for itself. Otherwise, just ask.
Listen carefully at first and you can hear them coming.
Our driver was nice enough to give them some money for food.
Indoor food market: