A tire tread having a tread surface (20) in the new state and at least one wavy groove (1) opening into the tread surface, the groove is the new state having external cavities (11) that open onto the tread surface in the new state along a length (Le) and internal cavities (12) that do not open onto the tread surface. The external cavities (11) have a bottom (110) of which the points that are innermost in the tread are at a distance (H1) from the tread surface (20) in the new state, the internal cavities (12) having a bottom (120) of which the innermost points are at a distance (H22) from the same tread surface (20). The external cavities (11) and the internal cavities (12) being connected together by linking cavities (13). The tread (2) being such that at least two sipes (31, 32) are formed from the bottom (110) of the external cavities (11) and along an entire length (Le) of these external cavities (11).