In this experimental investigation, mean liquid velocity fields were investigated for turbulent flow within a horizontal 7-rod bundle geometry using Particle Image Velocimetry (PIV). PIV measurements were conducted at two axial locations, near the bundle inlet and also near the mid-plane, and at four Reynolds numbers ranging from approximately 8400 to 21000 based on a hydraulic diameter of 7.636 mm. The axial velocity fields in three different gap regions of the 7-rod bundle were reported, including rod-rod gaps and rod-channel gaps. Statistical techniques were used to describe the velocity fields, including mean and turbulent velocity components. The instantaneous and ensemble-averaged velocities in the gap regions are shown to be aligned in the axial (horizontal) flow direction, with a negligible mean vertical components. It was found that the maximum velocity profile was between 20 to 25% higher than the average velocity, while measured axial turbulent velocity typically ranged between 10 to 20% of the corresponding mean velocity. Profiles of local mean and turbulent velocity components in the gap regions were found to be self-similar when normalized using the maximum velocity, and local velocity, respectively.