Algonquin Radio Observatory (ARO) is a radio observatory located near Lake Traverse, Ontario, Canada. Its main instrument is a 46-meter (150-foot) fully steerable radio telescope which has been in operation since 1966. The Algonquin Radio Observatory was used in the first successful very long baseline interferometry (VLBI) experiment in 1967. It was also used, by Alan Bridle and Paul Feldman in 1974, for the first SETI search to be carried out at the 1.35-centimeter wavelength, emitted by water molecules in space.