The High Energy Stereoscopic System (H.E.S.S.) consists of four 12m diameter imaging Cherenkov telescopes, and is presently under construction in the Khomas Highland region of Namibia, 1.8 km above sea level (23∘16′18′′ S, 16∘30′00′′ E). The H.E.S.S. telescopes provide very good angular resolution and background rejection capability resulting in a sensitivity ~ 10 mCrab with an energy threshold of around 100 GeV. The first two telescopes are currently operating, and the array will be complete in early 2004. This paper provides a description of the H.E.S.S. telescopes and reports preliminary results obtained with the first telescope. PACS: 95.55.Ka X- and gamma ray telescopes and instrumentation – 95.55.Pw Astronomical observations: gamma ray