By the early years of the 20th century, Boyce had become a multi-millionaire and had taken a step back from his businesses to pursue his interests in civic affairs, devoting more time to traveling and participating in expeditions. In 1909, he embarked on a two-month trip to Europe and a large photographic expedition to Africa with photographer George R. Lawrence and cartoonist John T. McCutcheon. Over the next two decades, Boyce led expeditions to South America, Europe, and North Africa, where he visited the newly discovered tomb of King Tutankhamun.