1. A computer-readable medium containing software that, when read by a computer, causes the computer to perform a method for wide-area site-based surveillance, the method comprising: receiving surveillance data, including view targets, from a plurality of sensors at a site; synchronizing said surveillance data to a single time source; maintaining a site model of the site, wherein said site model comprises a site map, a human size map, and a sensor network model; analyzing said synchronized data using said site model to determine if said view targets represent a same physical object in the site; creating a map target corresponding to a physical object in the site, wherein said map target includes at least one view target; receiving a user-defined global event of interest, wherein said user-defined global event of interest is based on said site map and based on a set of rules; detecting said user-defined global event of interest in real time based on a behavior of said map target; and responding to said detected event of interest according to a user-defined response to said user-defined global event of interest.