ISBN-13: 9780811726320 / Angielski / Miękka / 2004 / 248 str.
Features Last River Caverns, Crystal Cave, Indian Echo Caverns, Woodward Cave, Penn's Cave, Indian Caverns, Lincoln Caverns, Coral Caverns, and Laurel Caverns and includes ice mines, coal mines, boulder fields, and rock citiesDetailed history of each caveLegends and local lore of many features and sitesA roadside travel guide to and history of Pennsylvania's nine commercial caves and a wealth of other geographical sites within the state.