Borden, a relative newcomer, and Brucker, a veteran explorer, bring a personal and sometimes conflicting view of their roles as adversaries in a race that lasted from 1972 through 1983 to find "big cave". They describe hazardous adventures, precarious climbs, and close calls from falling rocks. The perils are many and the trek arduous as they squirm through muddy tubes, wade in neck-deep cold water, and crawl over sharp rocks and gritty sand. Theirs is a tale of agonizing endurance spiced by spectacular discoveries.

But the cave was not the sole obstacle. The explorations were complicated by political intrigue and the rivalry between the Kentucky-based Cave Research Foundation and the Central Kentucky Karst Coalition, each seeking to make discoveries and hide secrets. Extreme stress, of course, evoked extreme behavior, ranging from selfishness to sacrifice, from outrageous humor to the deadly serious response.

Beyond Mammoth Cave includes maps by Patricia Kambesis that show the progression of cave discoveries in relation to the topography. Original line drawings by well-known illustrator Linda Heslop capture the dark mystery of the exploration.

A sequel to The Longest Cave by Brucker and Richard A. Watson, this book is a comprehensive update of the speleological investigations in the Mammoth Cave region. Brucker's involvement provides continuity to the investigation.