The Karl G. Jansky Very Large Array is twenty-seven 25-metre radio dishes arrayed in a Y-shape across the Plains of San Agustin, 30 miles east of Datil on US-60. Operated by the National Radio Astronomy Observatory, it is one of the most productive radio telescopes ever built — the antennas are mounted on rails and physically moved every few months between four configurations, the largest spanning 36 km, to vary the resolution of the synthesised image. The high, dry, electrically quiet basin between the San Mateo and Magdalena mountains is one of the best radio sites in the world.
The site is open every day from 8.30am to sunset for self-guided visits. The visitor centre has a short film (narrated, when this was written, by Jodie Foster) and a walking trail that takes you right up to the base of one of the dishes — close enough to feel the size of the thing. On the first Saturday of each month there are free guided tours led by NRAO staff. The drive in from Datil along the empty straight road across the plains, with the dishes growing slowly on the horizon, is half the experience.