While most traffic into the depths of the earth tries to stick to the primary passages, there are those who wish to travel either to less-ventured places off the main passages, or those who wish to avoid running into major patrols of the various races down below.

Secondary passages are generally 20 feet wide and have fewer worked areas than the primary passages. The roof varies from 15 to 40 feet above the floor, with 25 feet being usual.

In addition to being smaller and less worked, secondary passages often have more obstacles than the primaries, as the “civilized” denizens of the underdark have had less reasons to build over or around them, or have stopped using the tunnel completely because of the obstacles.

The original sample secondary passage from Descent into the Depths of the Earth has been redrawn on the far left, and is now joined by 4 additional sample passages.

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