In February 2003, a Boeing 737-700 completed 11 test flights at Paro International Airport in the kingdom of Bhutan, high in the Himalayan Mountains. The rigorous test flights proved that the 737-700 is capable of meeting all performance and procedural requirements for safe operations at airports in high-elevation, high-terrain environments. The demonstration airplane was a 737-700 Boeing Business Jet (BBJ) configured with blended winglets and a business jet interior.