SEST, the Swedish-ESO Submillimetre Telescope, is a 15-m diameter high-frequency radio telescope situated at the ESO (European Southern Observatory) observatory on Cerro La Silla in the Chilean Andes. It was built in 1987 and was equipped with heterodyne receivers for operation between 70 and 365 GHz. It was the only telescope to operate at these frequencies in the southern hemisphere. Its 37-channel hexagonal bolometer array, SIMBA (Sest IMaging Bolometer Array), operated at a wavelength of 1.2 mm. Although the telescope still stands, it ceased operations in 2003.