Caulfield Racecourse hosts some of the most exciting races in the country, but it is a well kept local secret that it is actually public parkland. Use the racing track itself for jogging or walking the dog, and plan a picnic or BBQ in the by one of two man made lakes (which you can actually fish in).
Keep in mind the space is closed on racedays. Access via Queens Ave, Glen Eira Rd or Neerim Rd.