The resonance coupling between two adjacent inlets is investigated. Field evidence of this natural phenomenon is found for two elongated inlets in the region of Ciutadella, Menorca Island, in the Western Mediterranean (Ciutadella and Platja Gran). To illustrate the fundamental features of the problem, analytical solutions for two rectangular inlets with constant depth are constructed and analyzed. The theoretical results mimic well the field data and demonstrate the resonance coupling characteristics of the inlet responses. The phenomenon is also examined with a numeric model so that the effects of real bathymetry can be considered. Numerical computations show the specific resonant features of local topography and the agreement between field data and numerical results is very good.