In 2007, KTIMATOLOGIO S.A (Hellenic
Cadastre) established HEPOS, the HEllenic
POsitioning System, to facilitate the cadastral
activities in Greece. The system supports
network-based techniques like VRS, FKP and
MAC and has already proved its high potential.
At the same time, HEPOS modernizes the
geodetic infrastructure of the country. The
coordinates of the 98 reference stations of the
network are determined in ETRF2005. Thus,
the geodetic reference frame of HEPOS
(HTRS07: Hellenic Terrestrial Reference
System 2007) is a realization of ETRS89. A
national GPS campaign was carried out and a
coordinate transformation model between
HTRS07 and the Hellenic Geodetic Reference
System of 1987 (HGRS87) was estimated.
This report describes these activities.