The grain size of sediments from shallow boreholes (1–4 m) was used to determine the origin of four landscape elements on Point Pelee, southwestern Ontario. The sand plains, an area of low relief near the interior of the point, are composed of sediments derived from the lake floor and washed onto the Pelee–Lorain moraine by rising postglacial lake levels. The dune and beach ridge formations on the western flank of the point were built in the last 1000 years, with sediment eroded and moved alongshore from the bluffs to the north. The presence of several truncated ridges at the southern end of the enclosed marsh was confirmed. A new theory for the development of Point Pelee is proposed, in which alongshore transport of material is considered to be insignificant during the initial development of the point, but dominant during its later history.