Estuarine dynamics in tidal inlets is studied based on data of two measurement campaigns in the German Wadden Sea. We present the first direct observations of tidal straining in the Wadden Sea. We also observe asymmetric lateral circulation, which is generated by a systematic interplay of horizontal density gradients and centrifugal forcing. This process is found to be responsible for residual estuarine exchange flow. Finally, an idealized model is developed to study the relevance of this process for other systems.