What is a monorail?

A monorail is a guided transport system where vehicles travel on one rail or a single beam rather than on two traditional tracks. Some monorails straddle a beam from above, while others suspend the cars beneath it. The concept dates back to the 19th century, and monorails have been built in cities including Tokyo, Seattle, and Chongqing. They are often chosen where elevated routes, tight curves, or limited ground space make them practical. Although monorails can be efficient in certain settings, they are less common than conventional rail systems.