Families will have the opportunity to take part in the Greenway geoteaming competition at Rattlesnake Lake on Saturday, June 28, during the fifth annual Greenway Days, a weekend-long celebration of the 100-mile stretch of the Mountain to Sound Greenway.

Registration for the event is free; however, Mountains to Sound Communications Manager Amy Brockhaus encourages those interested in participating to register early.

“It’s become very popular over the last several years,” she said.

The family-oriented geoteaming event provides participants with a GPS unit, pocket PC and digital camera to document their cache discoveries. Random prize drawings will be awarded to geocaching team members. The object of the game is to locate as many hidden caches as possible along the trails at Rattlesnake Lake, said event coordinator Kelly Cundiff.

“We’re proud and excited that people really enjoy the event,” she said.

The geoteaming program is sponsored by Mountains to Sound Greenway, Girl Scouts of America and Playtime Inc., which provides the technology for teams to successfully complete their missions. The company hosts corporate team-building events around the world using the technology and geoteaming game to create stronger bonds among coworkers.

Other Greenway Days events, taking place over the weekend of June 28 and 29, include Cedar River Watershed Tours, guided hikes up Cedar Butte/Little Si and the Rattlesnake Mountain Traverse, bike rides from Rattlesnake Lake to Snoqualmie Pass and Fall City to Rattlesnake Lake and train rides at the Northwest Railway Museum. The 100-mile Mountains to Sound Relay takes place on Sunday, June 29. On both days, the Greenway Challenge has participants take photos at five to 10 Greenway sites.

Register at mtsgreenway.org/greenwaydays.