Flexural waves related to the ocean swell are identified more than 600 km from the open sea in the Ross Ice Shelf, Antarctica, where the ice cover is in places more than 500 m thick. An equation relating the power spectra of the flexural wave and the ocean swell is derived, based on the continuity of pressure in the fluid layer across the ice front. Correcting for the effect of the ice, the power spectrum of the wave in the ice compares to the ocean swell elsewhere in the Pacific Ocean.