Currently all caves in Saint Paul are abandoned and potentially hazardous and are closed to the public for your protection.

Along with the many fossils that are found in the Brickyard there are also caves in the area. Most of the caves (they really should be referred to as mines, as they are all man-made) occur in the St. Peter Sandstone Formation. The soft white sandstone is very pure, and contains very little impurities or cementing agents, which make mining comparatively simple.

The caves were used as mines in the early 1900s, and later used for growing mushrooms and making cheese. Echo Cave is one of the many man-made caves previously used for storage by the Twin Cities Brick Quarry. Now Echo Cave is currently used as the winter hibernation quarters for the Big Brown Bat species.

When dormant, bats are helpless and they are easily disturbed by the presence of people. Such disturbances may cause their death. The "bat" gate at Echo Cave has been erected to protect the bats in their hibernation. It is for this reason that this particular cave is closed to unauthorized human visitors.