The ocean and the marsh leave only a narrow strip of sand. A natural defile through which we can only send one regiment at a time.

8 seconds sound clip from the Glory (1989) movie soundboard.

You can hear this line at 01:28:44 in the Blu-ray version of the movie.

Quote context

[...]

- Wagner mounts a 10-inch Columbiad, three smoothbore 32-pounders, a 42-pound carronade, a 10-inch coast mortar, and four 12-pound howitzers plus a garrison of about a thousand men.

- As many of you gentlemen may be aware, for the last four days, our Navy has weakened Wagner with a constant barrage.

- Headquarters has determined a time for our attack.

- We will proceed with a direct frontal assault tomorrow at dusk.

- The problem, gentlemen, is the approach.

- The ocean and the marsh leave only a narrow strip of sand. A natural defile through which we can only send one regiment at a time.

- Our best hope is that that leading regiment can keep the Rebs occupied long enough for reinforcements to exploit the breach.

- Needless to say casualties in the leading regiment may be extreme.

- General Strong. The 54th Massachusetts requests the honor of leading the attack on Fort Wagner.

(Civil war cannon fire)

[...]