An article published today in the Journal Nature Human Behavior (here subscription requited) establishes the date of some of the Kimberly rock art paintings as 17,000 years ago.
Rock art is notoriously hard to date. The authors of the study took radio carbon dates from wasp nests built on top of paintings to establish minimum dates. One painting in particular is dated to between 17,500 and 17,100 years ago by dating material in overlying and underlying nests.
CNN provides and excelent synopsis here.