The Pierre Auger Observatory in Argentina will cover 3000 square kilometers when completed in Mendoza Province, Argentina. The observatory will be in the form of a large array of 1600 surface detectors (“water Cherenkov counters”). These devices will be used to detect the highest energy particles in the Universe, but they are very rare – hence the need for a large array. In fact, a similar array is planned to be built in Colorado, US. In addition to the array, there are four nitrogen flourescence telescopes, and two central laer facilities used to fire laser shots in the night sky to calibrate the detectors.
Stephane Coutu, an Associate Professor of Physics at Penn State University, posted a collection of placemarks documenting the detector array and other elements of the operation. There are scientists from 19 countries collaborating in the project. Look at the placemarks here . At this web page you can see more information on the Pierre Auger Observatory and the use of GE to visualize the project. They also have some 3D models of some of the buildings viewable with GE 4, for example: Campus buildings , Laser Facilities , and Flourescent Detector Buildings .
You can see some of the detectors in a few high resolution satellite photos of the area. However, Stephane notes that some of the photos appear to be incorrectly projected, or incorrectly placed. So, you see the detectors up to 50 meters away from the placemarks. In addition, not all of the detectors are built yet, so in many cases you won’t see a detector at the placemark.