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High-resolution particle image velocimetry measurements are made in the streamwise–wall-normal plane of a zero-pressure-gradient turbulent boundary layer over smooth and rough walls at Re θ≈ 13000⁠. The roughness considered herein is replicated from a surface scan of a turbine blade damaged by deposition of foreign materials and its topography is highly irregular and contains a broad range of topographical scales. Two physical scalings of the same roughness topography are considered, yielding two different rough surfaces: RF1 with k= 4.2 mm and RF2 with k= 2.1 mm⁠, where k is the average peak-to-valley roughness height. At Re θ≈ 13000⁠, these roughness conditions yield k+≡ k∕ y*= 207⁠, δ∕ k= 28⁠, k s+= 115⁠, and δ∕ k s= 48 for RF1 and k+= 91⁠, δ∕ k= 50⁠, k s+= 29⁠, and δ∕ k s= 162 for RF2 (where δ is the boundary-layer thickness, k s is the equivalent sand-grain height, and y* is the …