We had heard there was an incredible waterfall somewhere deep in the Thai rainforest. Seeking it out almost killed me.

In 2003 I was travelling solo through south-east Asia when I met Paul, an American with an easy-going, natural warmth. We were the only two people bunking at a youth hostel somewhere in southern Thailand and got chatting one morning. When the staff told us about a beautiful waterfall not far from where we were staying, we made plans to hike there together.

It was only meant to be an hour’s walk away. Thinking we would be back in time for lunch, we didn’t bother to take any food with us. Big mistake.

For four hours we walked through dense foliage, even climbing down vines in search of this supposed waterfall. At many points it occurred to us that we might be lost, but the naivety of youth propelled us forward. Eventually, the forest opened up to reveal a glistening pool of water with a waterfall at one end.…