Based on the comparison of strait-fill successions and modern examples, tidal straits are suggested to be composed of four main depositional zones: (i) the strait center, which is the narrowest or shallowest part of a strait, where tidal currents reach peak velocity, sedimentation is reduced to zero and by-pass conditions dominate; (ii) the dune-bedded zones, corresponding with two wider areas where tidal currents decelerate and sedimentation produces a spectrum of bedforms whose size scales with the decreasing flow strength; (iii) the strait-end zones, representing the peripheral exits of a strait towards open-marine conditions, where currents slow down until they stop and reverse, for initiating a new tidal cycle; and (iv) the strait margins, where river floods, waves, delta progradation and rock collapses from steep cliffs are processes interplaying with the strait hydrodynamics, generating specific accumulations.