There is a sign posted near the pier pointing the way to ‘Long Beach’ with no further comments or warnings.
I will comment and warn you that it is absolutely necessary to wear proper shoes. It is a hike, rather than just a walk and begins very steeply uphill where you will use your hands at time to help prop you up to the next rock. The path is not marked very well and there are chances to get lost but by fluke we made it on the first try.
The very first fork you meet you must continue LEFT following the path that passes by a house right away. There is the odd marker along the way and if you keep your eyes out you will see some old (probably tourist forgotten) flipflops ranging from children's to adults that are put in place to let you know you are going in the right direction along the way.
The hike stays fairly flat for about 25-30 minutes through the jungle before hitting your decent. The decent is much longer than your initial climb and ranges from areas where you must repel with assistance from a rope to just some steep steps and uneven footing. Eventually you will reach a sign that says Long Beach is 15 minutes away. I’m not sure who timed that but from there it took us about 30 minutes to the ground.
Once you are there it is spectacular. If you look closely at the photo you will see the beach continues much further than the eye can see wrapping around to the left tip of the island.
The only people who were on the beach when we were there were a few nomads/expats who have made camp on Long Beach and are currently living there in hammocks and hand built structures from palm trees near by. We stayed a few hours, watched the sunset and took a shared water taxi back to the pier. It is very rare for something so beautiful to be so completely secluded and untouched by tourism and development. Enjoy, take care and leave nothing behind.
Check out our video about cambodia to see amazing footage of KohRongIsland in the second half and the hike to Long Beach.