Crumbling stone slabs formed the broken walls of a ruined shelter in Savage Park, the floor was carpeted with dead leaves and twigs embedded in hardened mud.
Three men clutched their GPS electronic navigation units as they strode into the wall-encircled clearing. Their searching gazes suggested they weren't far from their goal.
Jason Ashmore's eyes scanned every crevice in the stone walls. He paused and suddenly bent down, reached into a hole under a stone slab and pulled out a white plastic container marked in bold black letters, "GEOCACHING.COM."
It was full of junk - a plastic Darth Vader figure, a heart-shaped eraser and a McDonald's Happy Meal toy - but Ashmore held it like a treasure. His father, Wayne Ashmore of Lansdowne, took a small notebook out of a plastic bag in the container and read aloud the adventures of other successful searchers. Each entry was dated and signed with a pseudonym.
The Ashmores and their companion, Randy Berry of Crofton, are passionate participants in geocaching, a fast-growing sport that sends people on treasure hunts equipped with only a Global Positioning System device and their sense of direction. Since it began several years ago in Washington state, geocaching has spread to 167 countries and as far north as the North Pole, said Jason Ashmore.
There are dozens of geocache treasures carefully hidden across Maryland, waiting to be discovered. They're all listed - together with thousands of other sites around the world - on the geocaching Internet Web site, www.geocaching.com, along with the chronicles of successful and not-so-successful treasure hunters.
For many geocachers, the experience is not about the treasure. It is about exploring remote parkland and landmarks that a person usually wouldn't visit, such as the wooded pathways on the outskirts of Savage Park in southern Howard County.
"It's usually about the difficulty and the quality park it's in," Jason Ashmore said. "It becomes less and less what you find as opposed to making the find."
Geocaching emerged several years ago on the West Coast after the federal government freed the Global Positioning System from selective availability (SA), which had limited GPS unit accuracy.
Under SA, the government purposefully scrambled location information provided by a satellite before it was intercepted by GPS units.
"They changed the code slightly so instead of being 20 feet off you were 100 feet off," said Berry.
After the SA was lifted and coordinates became more accurate, the sport spread quickly across Maryland, but not without some hitches.
In the summer of 2001, a geocacher tied an ammunition can to the supports of a railroad track in Patapsco Valley State Park and failed to identify the can as a geocache, according to Berry.
Unaware of the new sport, park rangers called in the FBI and the bomb squad to respond to what they believed to be an explosive. It cost the state almost $30,000, he said.
"A little bit of communication up front could have eliminated that to begin with," said Gary Burnett, manager of the Patapsco park. "It helps for us to have as much information as possible so that people won't get alarmed when they find something, and we won't have to call out the bomb squad."
That incident led Berry to found the Maryland Geocaching Society as a go-between for geocachers and the Maryland State Forest and Park Service.
"Our mission is to keep the parks informed," he said. "I decided that I would be a liaison so that there was someone who stood for cachers." He wanted to show the park service that there are geocachers who are responsible and cognizant of state security needs.
To garner the support of state officials, the Maryland Geocaching Society tried to get them personally interested in the sport.
"We took a couple of them out caching and a lot of them wanted to get involved themselves," said Robert McDonough, a Columbia resident and group member.
After beginning with a cluster of five to 10 geocachers, the society has grown to 125 members and is adding one to four people each week, said Berry. Of course, you don't have to be a member to go geocaching.
"We've managed to get an accepted set of guidelines and an application to hide a cache," Berry said. "We are the first organization to get an adopted set of guidelines."
Geocaches must be clearly identified, transparent Tupperware containers and must be approved by the state park service before they are hidden, Berry said. Geocache owners are encouraged to monitor their geocache's condition to ensure the environment around it is not trampled or destroyed.
Within the state, geocaching is most popular in Howard and Baltimore counties, particularly the caches in Patapsco State Park, Berry said. In fact, the Patapsco multicache "Good Luck" is one of the most difficult caches in the area.
"For multicaches, you find one cache that will give you the coordinates to the next," said Jason Ashmore.
Other types of caches include traditional, virtual, micro and theme caches.