Just another IMDb series which didn't actually happen...
"The Adventurers" was proposed as a 1968 series - a pilot episode was produced (episode title: "Once Upon A Map"), and a press release was issued claiming overseas sales and a 39 episode production run.
It was listed as a series (based, it seems, solely upon the 1968 press release) in a book on Australian television in the mid-90's, and has become accepted as fact.
Despite that, there's no record of the "series" ever proceeding past the pilot - no production stills (other than those from the pilot), no episode titles, no air-dates, no listings in TV guides of the time, no contemporary press reviews of the series, and no footage (other than from the pilot).
The basic concept finally surfaced a year later as "The Rovers".