I learned recently about where one of the scenes in "Raiders of the Lost Ark was actually filmed"

 It was filmed upriver from Kapaa. The ship captain of the shallow water barge told us about it as we sailed up this river to a nature preserve which is in a rainforest there. He showed us where on the river Indiana Jones was running from the natives and hopped onto a pontoon biplane. So, I guess they actually took off in this pontoon biplane on this river by Kapaa on Kauai. He named about 20 or more movies filmed on or near this side (the east side) of Kauai and up towards the Na Pali Coast of Kauai. 

Part of the reason is this is one of the rainiest places on earth on the Na Pali Coast and always lush and green year around from 500 to 1000 inches of rain coming down in the mountains nearby. So, the river next to Kapaa is always full because of this and very lush.