Andronikos of Kyrrhos was a Greek architect and astronomer. He is associated with a single building, the Tower of the Winds (Horologion) on the edge of the Roman agora in Athens, of which he was named the architect by Vitruvius (On Architecture I.vi.4). This elegant and ingenious small marble octagonal building was designed externally as a monumental sundial and weather-vane, with a representation of each of the eight winds carved on the sides of the octagon; at the apex of the roof was a bronze Triton that acted as a weathercock. The interior of the building contained a complicated waterclock; apart from the Triton and the clock, the building is well preserved. The date of the Tower of the Winds, and hence of Andronikos, is uncertain. The tower has usually been dated to the mid-1st century BCE, connecting its construction with that of the Roman agora and relying on the fact that the tower was mentioned by Varro (On Agriculture III.v.17) and Vitruvius, writing just after the middle of the century.