Luke Mueller of Park Hill, Colo., grandson of Norman and Vivian Mueller of Hillsboro, is part of a successful business of worldwide community service and global citizenship.

Created in 2005 in Park Hill by friends Mueller, Paul Laurie, and Gabriel Duncan-Roitman, Walking Tree Travel is more than a Denver-based youth travel and voluntourism agency. Its cultural immersion programs in Costa Rica, Senegal, China, Mexico, Nicaragua, Guatemala, and Peru have long-lasting effects on both travelers and host communities.

When not building libraries, helping to prevent malaria, reforesting fields, digging drainage systems, or teaching English in orphanages and monasteries, Walking Tree’s student travelers interact with new cultures via language immersion, home-stays with resident families, and traditional excursions to foreign destinations off the beaten trail of tourist traps.

To date, Walking Tree has facilitated the worldwide community service and global stewardship of nearly 1,000 travelers from several countries, 22 U.S. states, and 39 Colorado high schools.

Norm Mueller and Christy Murphy of Denver are Mueller’s parents.