Sweden to Host 'World's Deepest Marathon' in Mine 3,000 Feet Underground

Sweden to Host 'World's Deepest Marathon' in Mine 3,000 Feet Underground

With record-breaking summer heat becoming the norm each year, running endurance events beneath the beating sun becomes a tough — and dangerous — proposition. Just this spring, one runner died and others were hospitalized during a California half-marathon in May. Another died last year during a Disneyland half-marathon amid rising numbers of heat-related deaths in the U.S. Even Paris had to make big changes to ensure athletes didn’t overheat duri…