Arecibo Radio Observatory
by Tom_Fields
With a reflecting dish 1,000 feet in diameter, and a 900-ton receiver suspended 450 feet above it, this is the largest, most sensitive radio observatory in the world. It can detect radio signals from near-earth space and from billions of light-years away.The visitors center has a theater, small museum, and shop. Even if you're not a scientist, the place is a sight to behold. There is nothing else quite like it.This location was chosen because the exceptionally rugged karst country offered a natural valley sunken into it. It was just perfect. To get here from San Juan, follow Highway 22 west to Highway 651, and turn south. Follow the signs. It's located in a very scenic, out-of-the-way place, off a narrow, winding two-lane road. Be careful coming up.