 Omaha was bounded at either end by large rocky cliffs . The crescent @-@ shaped beach presented a gently sloping tidal area averaging 300 m ( 330 yd ) between low and high @-@ water marks . Above the tide line was a bank of shingle 2 @.@ 5 m ( 8 ft ) high and up to 15 m ( 49 ft ) wide in places . At the western end , the shingle bank rested against a stone ( further east becoming wood ) sea wall which ranged from 1 @.@ 5 – 4 m ( 5 – 13 ft ) in height . For the remaining two thirds of the beach after the seawall ended , the shingle lay against a low sand embankment . Behind the sand embankment and sea wall was a level shelf of sand , narrow at either end and extending up to 200 m ( 220 yd ) inland in the center , and behind that rose steep escarpments or bluffs 30 – 50 m ( 33 – 55 yd ) high , which dominated the whole beach and were cut into by small wooded valleys or draws at five points along the beach , codenamed west to east D @-@ 1 , D @-@ 3 , E @-@ 1 , E @-@ 3 and F @-@ 1 . 
