Complex sentence: It was formerly contested over 2 miles, 6 furlongs and 34 yards, but it was shortened as a result of the realignment of Ascot's track in 2005.
Split into simpler sentences: It was formerly contested over 2 miles, 6 furlongs and 34 yards. This was cut to the present length as a result of the realignment of Ascot's track in 2005.