Marathon running is having a landmark year. In April, the first official sub-two-hour marathon was recorded in London, helping propel the sport further into the global spotlight. This October and November, attention turns to the Chicago and New York marathons, two of the world’s largest races, attracting tens of thousands of runners and spectator crowds estimated in the millions., , , , New data from Amadeus Travel Intelligence reveals that travel indicators showing air and hotel demand are.....