[1] The entrance to Mushpot Cave is a hole in its roof, located in the parking lot that serves the Visitor Center and Headquarters building.

A staircase leads to the floor of the cave, and from this point one can traverse the main branch of Mushpot lava tube downstream (northeast) for 520 feet (160 m).

Only about 50 feet (15 m) of the length of this east flowing tube is visible because both upstream and downstream it is filled to its roof with congealed lava.

Filling a 3 foot (0.91 m) space between floor and roof of the tube is a jumbled mass of frothy and distorted lava blocks—the crusted-over surface of a moving flow that broke and stuck, creating a constriction comparable to an ice jam in an Arctic river after the spring thaw.

One high-lava mark is present 20 inches (510 mm) above the floor on the east wall of the tube in the alcove containing the Mushpot bubble.

These small patches of dripstone may be from lava that splashed up onto the wall by violent emission of gasses ("fountaining") of the flow that produced the high-lava mark.

[2] The high-lava mark downstream because it is covered or removed in places by collapse or by human activities connected with trail construction.