BUCKS COUNTY, Pa. (WHTM) — The Keystone State has a few giant collections of boulders and among them is Ringing Rocks in Bucks County. Families flock to the park each summer for both the sights and of course, the sounds.

Hammers, that’s what thousands of visitors bring to Ringing Rocks each year. “It is a really cool boulder field. The rocks ring like bells. Not all of them, but a lot of them,” Gail Hill from the Bucks County Department of Recreation said.

The kids know which rocks are more likely to ring. “The ones that are more white and that have dents in them pretty much,” Ryan of Williams Township said.

Experts say it’s certain rocks suspended on others that aren’t touching any soil that resonate most.

“It’s not just kids. Everybody loves it,” Hill said. “One time, I brought my mother here and she’s a musician, and she found a triad, a chord,” Tim Clarke of Upper Balck Eddy said.

The lay of the land contributed to how eight acres of rocks ended up bunched together in the village of Upper Black Eddy, near the Delaware River. “What they believe what happened is Bucks County, Montgomery County, surrounding county here were at the end of the ice age. The ice didn’t reach down this far but it pushed all these things down here,” Hill said.

Scientists believe between the freeze and the thaw the igneous rock broke apart. “This is about two million years old,” Hill said,

Once you’re done hammering away there’s more to see and do. Walking along the geologic wonder is a regular activity for locals Diane Alex and Tim Clarke. “Recently they’ve updated a lot of the trails. There’s one that goes already down to the river,” Clarke said.

The Delaware River. The couples describes this noisy spot that’s packed on the weekends and some weekdays as peaceful in the mornings. “I love the trees. I love the quiet,” Alex said. “It’s kind of a spiritual place,” Clarke said.

It’s history that every visitor values in their own way. “It’s actually really cool. They sound almost like metal,” Landon of Williams Township said. “People are intrigued by it, which they should be. I mean, the rocks in your yard don’t ring,” Hill said.

If you have extra time before heading home, there are more outdoor activities nearby. Ringing Rocks is one of 11 parks and nature centers in Bucks County.