The Kokoda Trail, which links the north and south of Papua New Guinea, have a very long history, beyond a history of being a difficult hike! The area was the scene of intense fighting between Australian and Japanese armies during the Pacific war periods of World War II.
Today, the 96km trail, which takes on average 11 days to complete, is attempted by many experienced trekkers. There are numerous organizations that attempt to lead hikes through the region, so you have many to choose from! The trail covers grounds that are rugged: mountainous country of rainforest, jungles of fern, orchids, birds and clean mountain streams which tumble into steep valleys.
What are the risks of this trail? Apparently, malaria, extreme heat, cold nights, and unstable terrain mean that only the brave should attempt to complete this 11 day hike.
To complete the hike successfully, you need to be prepared! The days are hot, the nights are cold, and you will get serious chaffing and mosquito bites. If you choose to go with a guide company (which I recommend) they will give you a list of things you should bring, but my research has told me that the list found here (http://www.kokodatrail.com.pg/preparation.html) is really thorough, and would probably have you over prepared! This specific company has you staying in villages in the area on some nights, so it also gives you a breakdown of how much money you might want to bring in order to participate in the local economy!
Please train hard before you attempt this trek as it is seriously full on, down hill is just as hard as up hill. Using a walking stick and gloves is my tip. Tape your feet before you get blisters and some pain killers or sleeping aids are a must for night time and rest.
If you do your research, this is a physically and mentally rewarding trip that can't be beat! If you're having trouble choosing an organizer, I recommend using sites like Trip Advisor and the Kokoda Track Authority (http://www.kokodatrackauthority.org/Kokoda-Track-Authority/Planning-your-Walk_IDL=1_IDT=1257_ID=5681_.html) to plan your trip!