Wikipedia gives some of his running history: “During a 44-day European tour in 1965, he competed 18 times and broke 12 world records, including the 20,000 m (just short of a half-marathon). He lowered his own 10,000 m world record by 39 seconds to become the first man to break the 28 minute barrier, running a 27:39.4. "To win against a field of kickers, Clarke needed a fast pace throughout or a sustained surge at the end. He improved his 2-mile speed in 1967 and 1968, lowering Jazy's world record by 3 seconds, running an 8:19.8 and then an 8:19.6."
Born Adelaide 1948. Moved to Canberra 1969. Married Jenny 1970. Three children - Nathan Moore, Loani Falconer, and Mon Hall; children-in-law Lisa Moore, Wes Falconer, and Scotty Hall. Thirteen grandchildren - Jackson, Tyler, Charlie and Samuel Moore; Kayleigh, Jarod, Alex, Olivia, Will, and Sophie Falconer; Josiah, Liana, and Amelie Hall.