FBN 2
FBN 2 : Federal Base Network. A nationwide, 100 kilometer array of permanently monumented stations. It provides spatial reference control that has some of the highest accuracies available. The FBN enhances the Nation's spatial framework for precision navigation, mapping, and resource management. Developing and managing the FBN is one of the primary responsibilities of the National Geodetic Survey (NGS), Looked it up elsewhere in the source