On September 13 at 1630 GMT watch "Expedition: Sumatra," a half-hour feature program with CNN Special Correspondent Philippe Cousteau.
Sumatra, Indonesia (CNN) -- Flying over the island of Sumatra in Indonesia, I looked out the window and got my first exciting glimpse of the Sumatran rainforest. It was vast, lush and green, but it wasn't all rainforest.
There were squares of farmland and large patches of trees in neat rows that I knew were palm oil or pulp and paper plantations.
From above, the patches of green seemed to flow in and out of the rainforest, but I knew those patches of rainforest were shrinking.
I turned around and saw that the other members of our CNN crew on the plane with me-- correspondent Philippe Cousteau, tech expert John Sanders and Hong Kong based cameraman Scott Clotworthy-- were all looking out the windows, too.
After all the preparation and the travel delays, we had finally made it. We knew this was going to be a trip unlike any other.
Our first destination was at a very remote camp in Jambi Province near 30 Hills National Park. I knew how remote it was going to be, so it wasn't a surprise when we traded our caravan of pickup trucks for three giant off-road vehicles.
We knew since we were here during the rainy season, these vehicles were the only way to get up these extremely muddy mountain trails.
I didn't know just how treacherous these trails would be until the driver of our off-road truck stopped and told us that we would have to cross the bridges on foot. If a bridge broke or the truck slid off, we didn't want to be inside.
It was dark, and the CNN U.S. crew didn't have our gear because our luggage was lost in transit. I was the only one with hiking boots and Philippe was the only one with a flashlight.
We eased out of the trucks into slippery, squishy mud and walked slowly toward the bridge trying to avoid deep puddles.
These bridges were a test of our balance and nerve. Each bridge was two sets of heavy logs lashed together, one set of logs for the left tires and one set for the right. We looked down and estimated it to be a 6 meter drop.
We slowly and carefully walked across one side, one at a time, tightrope style. Scott and John even did it carrying their cameras.
Amazingly, no one slipped. Even more amazingly, the trucks all made it across with no problem. I was still very glad to see the camp lights come into view.
We had finally arrived at the Frankfurt Zoological Society Orangutan camp. This group is doing some amazing work to help replenish a critically endangered Sumatran orangutan population.
Their goal is to take captive Sumatran orangutans that were pets and teach them how to live in the wild so they can be released into the rainforest.
Orangutans were extinct in this area of Sumatra before the FZS came here. Now, more than 140 live in this patch of rainforest.
Once the generator powered down for the night, I lay in my bed and listened to the sounds of the rainforest just outside. Soon it started to rain and the sounds of the rain mixed with the sounds of the rainforest were incredible.
I will never forget the sound of the Sumatran rainforest surrounding me, and the feeling of knowing the next day I would see a captive orangutan released back into the wild.