"There's a lot going on along this trail," said Jeri Jones, describing the 14-mile Northwest Lancaster County River Trail as it runs from Columbia to Falmouth. "There are so many cool things to see."

Jones combined his knowledge of the trail and his passion for geology to write "Geologic Guide to the Northwest Lancaster County River Trail." The book, which was published in 2020, provides an overview of 26 stops along the trail, beginning at the Columbia Crossing River Trails Center and ending at the Falmouth boat launch.

"There is no geological knowledge required to enjoy this book," Jones stated, noting that the book begins with what he calls "River Trail Geology 101," which introduces readers to types of rocks and geologic features such as faults and folds. "I know people who like to carry this book on the trail with them. It's a tool to enhance their trail walk and give them a purpose while they're on the trail."

The book was made possible with support from three sponsors - Susquehanna National Heritage Area, Jones Geological Services (Jones' Spring Grove-based business) and Rivertownes PA USA. Although it only came out last year, the book has sold well, Jones said, and it's already in its third printing.

The idea for the book came from Jones' own experience along the trail. "I'm an educational geologist, and I used to take field trips to the Chickies Rock area," he explained. "I wanted to share my knowledge of the area with people."

Chickies Rock is especially significant in geologic terms, he noted, because the outcrop is a classic example of an "anticline," or a folded arch. "This is really the best example of this in the mid-Atlantic states," Jones noted, adding that student groups from colleges throughout the region come to Lancaster County to study the site. A fossil known as skolithos was also discovered in the Chickies Rock area, he said.

Jones had been thinking about writing the book for years, but when he retired from the York County Department of Parks and Recreation in 2017, he finally got to work on it. "I decided, 'This needs to get done,'" he said. "I made it a priority."

Along with Chickies Rock, the book highlights the Haldeman Mansion, the Musselman-Vesta Furnace, Shocks Mills railroad bridge and the White Cliffs of Conoy.

In his 40 years of geologic research, Jones has written several other books, and he said his next project might be revisiting a topic he's covered in the past - where to pan for gold in southeastern Pennsylvania.

In the meantime, he invites people to pick up a copy of his river trail book and hit the trail. The book is available for sale at the Columbia Crossing River Trails Center, 41 Walnut St., and the Zimmerman Center for Heritage, 1706 Long Level Road, Wrightsville. It is also available by contacting Jones at jonesgeo@comcast.net or 717-887-7103.