The tours I wanted in Darwin with the sightseeing pass were not available on the days I needed them.I ended up having to take a tour of Litchfield instead of Katherine Gorge was ok but not really satisfactory.My choice left me with half a coupon unused.I asked AAT Kings if I could use the remaining half coupon to get. a BBQ dnner option added to the Uluru Sunset and KataTjuta tour which I had purchased individually but they weren't accomodating and referred me back to Viator which is just a waste of time and money.Tours were fine but customer service not stellar.