The Isle of Man Tourist Trophy motorcycle races, held each year, also attract visitors. The course consists of over 37 miles [over 60 km] of main roads. At the first race, held in 1907, the top average speed was under 40 miles [65 km] per hour. These days the winning average speed is over 120 miles [190 km] per hour. It is, of course, a dangerous sport, and over the years a number of riders have been killed.a