The Very Large Array is a major radio astronomy facility located on the Plains of San Agustin about 50 miles (80 km) west of Socorro NM. It is remote from any habitation and the nearest conventional railway is the BNSF at Socorro. Why, then, is it included in a website relating to railways?
The answer lies in the means used to move each of the giant antennae that make up the Array. The Very Large Array has 3 arms, each 13 miles (21 km) in length, arranged in the form of a Y. Each arm is equipped with a number of steerable dish antennae which can be disposed at various positions along the arms for performing different astronomical observations.
Each of the antenna dishes is 82 ft (25 m) in diameter and a complete antenna assembly weighs over 190 tonnes. They are moved using a specially laid double track railway line. In the picture above the double track on each arm can be clearly seen, as well as the curved track linking the arms together.
When the antennae reach their working positions, they are moved laterally on side tracks away from the double track main line. The side tracks can be seen in the above picture.