In this paper the influence of a wall on vortex shedding frequency, geometrical pattern, and velocity field are investigated. Frequency measurements were carried out with three circular cylinders at Reynolds numbers of 2860, 3820, and 7640. Mean and fluctuating velocities at several traverses were also measured at Re = 3820 both for an isolated cylinder and for an arrangement with a gap from the wall equal to one cylinder diameter. The modifications of the wake pattern are shown in several figures. It is also shown that the proximity of the wall induces a slight increase of vortex shedding frequency.