Complex sentence: Stage coaches started to bring tourists from Flagstaff to the Grand Canyon the next year--an eleven-hour greatly increased in 1901 when a spur of the Santa Fe Railroad to Grand Canyon Village was completed.
Split into simpler sentences: Stage coaches started to bring tourists from Flagstaff to the Grand Canyon the next year--an eleven-hour journey. Tourism greatly increased in 1901 when a spur of the Santa Fe Railroad to Grand Canyon Village was completed.