where was the movie thin red line filmed
Mostly in the  Daintree Rainforest and on Bramston Beach, both in north Queensland, Australia.
The Thin Red Line (1998 film)
"The Thin Red Line" was filmed predominantly in the Daintree Rainforest and on Bramston Beach, both in north Queensland, Australia. 
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The Thin Red Line (1998 film) [SEP] Principal photography
We would have had to bring everybody to Guadalcanal, and financially it just didn't make sense". "The Thin Red Line" was filmed predominantly in the Daintree Rainforest and on Bramston Beach, both in north Queensland, Australia. Filming also took place on Dancer Mountain, which had such rough terrain that trailers and production trucks could not make it up the hill. A base camp was set up and roads carved out of the mountain. Transporting 250 actors and 200 crew members up the hill took two hours. Filming took place in the Pacific Ocean off the coast of Southern California near Santa Catalina Island.