We describe an innovative regional GPS project that makes use of the same array of instruments to address a wide range of scientific problems. The primary application of the array is the precise, continuous monitoring of regional deformation in the area of western Crete, Greece. At the same time the fortuitous coincidence of one island site with a sub-satellite cross¬over point of the TOPEX/POSEIDON and JASON-1 missions makes that site an excellent candidate for an altimeter calibration for both missions, as well as many other altimetric missions (ERS-2, GFO, ENVISAT). Our contribution describes the present status of the array, first results from precise connections of the GPS sites with existing tide-gauges and our future plans.