WILLIAMSPORT, Pa. -- If you've taken a walk through downtown Williamsport recently, it's likely you have passed one of many colorful rocks without even noticing.
Hand-painted and purposely placed all over the city, the rocks are part of what's called "Wilpo Rocks" after one of Williamsport's nicknames.
"It's like a scavenger hunt, interactive, kind of keeps the city participating, makes the city more lively," said Rafael De Leon.
According to the Facebook page, anyone can paint a rock. Most are colorful and some have positive messages. Rock hunters are encouraged to keep the rocks or re-hide them for someone else to find.
"I'm sure Brandon Park has a bunch, a lot of trees and nooks," said De Leon.
A few of the summer campers we met at Brandon Park tell us they've found rocks there.
"It was last year and when we were walking to the car, I found it right next to that tree over there," Brielle Thornton, age 7, said.
We decided to try searching at the Hiawatha. That's where we met Kyle Jones.
"If I see one laying on the ground, I try to put it up against the tree so we don't hit it with the lawnmower or weedwhacker," Jones said.
Working maintenance for the Hiawatha, it didn't take long for Jones to find a rock to show us.
Jones says he's already found over 20 rocks. Rock hiders sometimes leave hints online.