The Wetumpka impact structure (near the town of Wetumpka, Alabama) has a semicircular crystalline rim that is ~5 km in diameter. This marine-target impact structure developed in both poorly consolidated, water-saturated sediments and underlying crystalline basement. Previous studies have described a semicircular, crystalline rim, an interior structure-filling unit, and an exterior disturbed terrain developed within the sedimentary target sequence outside the southwestern part of the central basement crater. Based on new field and drill-core observations, we recognize the following specific structural and lithological features: overturned crystalline rim flap; slumped interior megablock terrain; central polymict breccia (originating as near-field ejecta); interior marine chalk deposits and reworked glauconitic sands (formed by resurge and postimpact deposition); and a collapsed southern part of the rim with overturned flap (mainly developed within the sedimentary target rocks). In this paper, we describe the origin of these features and present a new reconstructed sequence of events.