What is the highest railway station in the world?

The highest railway station in the world is Tanggula Railway Station.

Tanggula Railway Station stands at about 5,068 metres (16,627 feet) above sea level in the Tanggula Mountains of Tibet, China. It is part of the Qinghai–Tibet, or Qingzang, Railway, which links the Tibetan plateau with the Chinese rail network. The station opened for service on 1 July 2006.

Tanggula is an unstaffed station with three tracks and a platform about 1.25 kilometres long. Its extreme altitude creates severe engineering and operating challenges, including thin air, freezing temperatures and permanently frozen ground. The railway was built with special measures to protect the permafrost beneath the track.

Several alternatives in this question are notable high-altitude places, but they are not the world record-holder. La Rinconada is a high settlement, El Alto is a high city, and Cusco is a historic Andean city. The nearby Tanggula Pass is even higher, at about 5,072 metres, but it is a railway high point rather than a station.