By Claire Marshall
BBC correspondent in Cuetzalan, Mexico
The route down to the cave complex in the remote region of Mexico where six British pot-holers are trapped is perilous enough by itself.
Heavy recent floods have turned pathways into treacherous sliding bogs.
This should be the dry season, but rain patters down onto the lush, green foliage.
The cavers refused help from local teams
At several intervals along the pathway to the cave complex stand Mexican soldiers, barely visible in their green fatigues among the trees.
They are working with the British military by securing the area so a rescue can be carried out.
It is the unseasonable weather which has caused the problems for the British six-man team, five of them thought to be members of the military, and their civilian guide.
They went in to explore what they believe could be one of the largest cave complexes in the world, an estimated 360km long.
It should have been a three-day mission, but when they tried to get out, their exit route was blocked by flood water.
John Taylor is a member of the exploration team.
He steps into his protective overalls and checks the light on his hard hat.
It is John's job to go just inside the cave entrance and call his friends stuck inside.
"This was always something that was envisaged," he says as he packs his rolling tobacco in a waterproof box, part of his "essential personal kit" that he is taking with him on this route.
The six men are trapped in the Cuetzalan cave system
"They're absolutely fine there, they've got sleeping bags and water filters and if necessary they can stay as long as it takes," he said.
The plan now is to wait until two expert divers, flown in especially from Britain, can assess whether they should stay and wait for the water levels to drop or to escort them out one by one under water.
Getting to the flooded cave entrance involves scaling very slippery rocks and squeezing through a narrow entrance.
The "front door" is a vertical drop down into a dark, boiling lake.
The sound of rushing water echoes around the walls.
Escorting this team to safety is an unenviable task.
The local people here are bemused by all the sudden attention being paid to their remote region.
Constantino, a farmer, stands in his thong sandals and traditional white cotton clothes, wearing a cowboy hat and with a machete swinging at his waist.
He watches the soldiers, police and journalists trek down to the cave.
I asked him whether many people had been lost in the caves of Cuetzelan.
He shrugged his shoulders and said, "They come, they walk by, they go in and who knows whether they come back?"