The study of the anisotropies of the Cosmic Microwave Background Radiation (CMBR) is one of the main topics of the modern Cosmology. After the detection by COBE (Smoot et al. (1992)) at angular scale, many experiments have been realized to measure these anisotropies at smaller angular scales (Cheng et al. (1995), de Bernardis et al. (1994), Ganga et al. (1994), Gundersen et al. (1995), Hancock et al. (1994), Netterfield et al. (1995), Ruhl et al. (1995)). A turning point for such studies will be the realization of satellite missions, which are presently being developed, such as MAP (Bennet (1996), Mayer (1997)) and Planck (COBRAS/SAMBA, Report on Phase A Study (1996), Mandolesi (1997), Puget (1997)). They will be able to map the anisotropies of CMBR at all angular scales larger than 10 arcmin in several observing bands.
Observations of CMBR anisotropies will make possible the determination of many fundamental cosmological parameters, such as , , . Therefore it will be possible to investigate the very early phases of the evolution of the Universe.
Such measurements are severely constrained by atmospheric transmission and turbulence (the so-called sky-noise), especially from ground-based sites but also at balloon altitude. On the other hand, satellite missions are very expensive. It is therefore important to select the best observing sites for ground-based observations, for planned and future projects of large telescopes and long integration observations.
In the recent past a large effort has been made by some scientific groups to asset the potential for submillimetric and millimetric observations of the high Antarctic Plateau (Burton et al. (1994) and references therein). This continent appears to have the best observing conditions in this wavelength range, due to its dryness, steady air and isolation from man-induced pollution.
The Italian Antarctic Program started the realization of a permanent station at Dome C, on the high Antarctic Plateau (Concordia Project). In December 1996 was possible to set up some light experiments at this site, taking advantage of the simple logistic facilities already available for scientific activities.
The APACHE96 experiment has been realized to make observations of the CMBR anisotropies and to test the potential of Dome C for millimetric observations. The first observing campaign was carried out in December 1996--January 1997.