Creg Willey's Hill (Manx: Creg Willy Syl - Willy Sylvester's Rock) is situated at 10th Milestone road-side marker between Glen Helen and Sarah's Cottage on the Snaefell Mountain Course used for the Isle of Man TT Races on the primary A3 Castletown to Ramsey road in the parish of German in the Isle of Man.
Creg Willey's Hillclimb is a motor sport event run by the Manx Motor Racing Club held on a short stretch of the TT course approximately 1.45 miles (2.33km) in length. The participants run singly in the timed event starting at Glen Helen, then negotiate Creg Willey's Hill, Sarah's Cottage and Lambfell before finishing on the Cronk-y-Voddy Straight.
Creg Willey's Hill was part of the Highland Course and the Four Inch Course used for the Gordon Bennett Trial and Tourist Trophy automobile car races held in the Isle of Man between 1904 and 1922. It was also part of the St. John's Short Course used between 1907 and 1910 and part of the Snaefell Mountain Course used since 1911 for the Isle of Man TT Races and 1923 for the Manx Grand Prix.
Coordinates: 54°13′51″N 4°37′03″W / 54.23083°N 4.61750°W