Every year, Oregon’s Lincoln City, on the west coast of the United States, organizes a treasure hunt where more than 3,000 handcrafted glass orbs are hidden on public beaches for people to find. The orbs come in a range of sizes—from the size of a baseball to as large as a basketball. They are hollow and are decorated with colorful swirling patterns.

The Finders Keepers treasure hunt has been an annual event for the last two decades, but there was a time when nobody had to hid glass balls on the beach for others to find. These balls came naturally from the ocean, usually after the winter storms, and were—and still are—prized items among collectors. They are called Glass Fishing Floats, and were once used by fishermen in many parts of the world, most notable in Japan and Norway, to keep their fishing nets afloat.

Photo credit: www.glassfloatjunkie.com