Trench is NOT a gaming level - it is basically a utility level.
Purpose: to help wad authors determine if the player will be able to 
make a jump or not. I often see this kind of request on RGCDE.

Description:
This is a level 1 for DOOM II.
TRENCH.WAD can be used Single player, Cooperative and Deathmatch
(Sometimes people might want to see how a jump looks from the side)
I could not help but add a nice texture (credit to MicroProse) and 
some nice music (credit to Queen) and a sound (credit to Raven&ID)
Level contains no demos.

Operation: 
Switch with red arrow will lower the opposite side of trench all way 
down. 
Switch with green arrow will raise it in increments of 32. Thus, one
may vary the difference of jumping height. The texture used allows to
determine quickly the height difference. Total depth is 512, each square
is 64.
Trench width changes in 32-point increments, from 32 to 512. Again, floor
texture allows easily to determine the width used.
To facilitate more accurate jumping, guiding 'rails' are provided. The
runway length is also easily determined using floor texture.
For your convenience, a teleporter is placed in the trench corner for
easy exit.

Oh, and if you get sick of jumping, go and slug it out with a cyber!
Hope that you'll find this wad helpful.