Horizontal bending of long range underwater sound rays can be caused by repeated reflection from a sloping sea bed, and in a previous paper the author used ray invariants to calculate the horizontal projection of ray paths analytically. At low frequencies ray‐mode equivalence imposes restrictions on the initial ray elevation angles, which in turn cause shadowing in the horizontal plane. Analytical ray paths and shadow zone boundaries are derived here in a simple way for some bottom topographies of interest including a wedge, a ridge, and a seamount. Horizontal shadow zones have important implications for hydrophones near the edge of the continental shelf because the shadows are well developed in shallow water and may easily extend into deep water.