Jon and Gendry were ranging out in front of the rest when it happened. One moment they were on solid ground, trudging through the snow, several paces from each other, the next the earth had shifted.

There was a sharp crack and Jon felt his feet go out from under him as he fell, snow billowing around him, covering his vision. Panic rose as he dropped through the air, but seconds later he thudded to the ground, falling heavily on his side. He heard a sharp cry from Gendry as he hit the ground nearby. Snow was still falling in on top of them, but less now. Jon struggled to sit up, glancing wildly around himself. He looked up and saw a silhouette of sky several spans above, through a hole in the ground. With a sharp curse he realised what had happened. They'd fallen through a thin patch of snow and ice covering an entrance to the underground cave systems that littered the wilds.

All around them was darkness, lit dimly by the shards of cold, clear sunlight from the hole. Jon pulled himself to his feet and scanned around, not seeing Gendry. His heartbeat sped up as he called out in a low voice, careful of triggering more snow in on their heads.

'Gendry? Gen? Where are you?' There was no response to his words and thoughts started to race through his mind. He'd heard Gendry cry out as he fell, but what if he'd landed badly? What if he'd broken his neck? What -

With a sharp exhale of relief, Jon saw a mound of snow off to his left shift slightly and he hurried over, plunging his gloved hands down into it. He felt the smith's broad, muscled shoulder and grasped his furs hard, grunting as he pulled him up into a sitting position, snow cascading off him.

Gendry gasped and panted, looking around himself with wide, panicked eyes. Jon grasped him by both shoulders, kneeling in the snow in front of him. Gendry locked on Jon's face and seemed to calm down. He closed his eyes briefly, forcing himself to suck deeper, slower breaths. Then he opened them and met Jon's concerned gaze.

'What the fuck just happened?' Gendry rasped.

'We must have hit a thin patch in the ice cover' Jon responded. 'There's thousands of miles of caves and tunnels spread all over this land. Entrances pop up everywhere if you know where to look ...' Jon broke off, thinking of Ygritte and others in this land who'd known its secrets. He was about to ask Gendry if he was ok when a voice interrupted them.

'You two alright down there?' It was Berric, poking his head gingerly over the edge of the hole to peer down in at them. Even his small movement caused clumps of snow to fall down, plopping wetly. Jon started, realised he was still grkipping Gendry's shoulders, and pulled away, brushing one hand through his shaggy black hair to dislodge more snow.

'Fine,' Jon called back up to him.

'Alright, I think,' said Gendry, examining himself. 'I've scraped my arm on something I think but it's fine for now.'

'Good,' said Berric. 'Bloody lucky if you ask me. Now how are we going to get the two of you out of there? You're a fair way down, much further than our rope will reach. Is there anything you can climb up on?'

Jon stood, reaching a hand down to Gendry who grasped his firmly and pulled himself to his feet. They both looked around themselves in the dim light. The walls around them were sheer and glossy with no handholds of any use. Ahead and behind them a tunnel stretched into the distance, quickly becoming lost into the darkness.

'No. Nothing,' Jon called back up, stomach twisting. Gendry moved in beside him, bumping his shoulder gently.

'What are we going to do?' He murmured, shooting Jon a worried glance. Jon frowned, thinking hard.

'Chuck us down a torch,' he said to Thoros, who had now joined Berric and Clegane in peering down at them. The two of them waited a few moments, still standing closely together, and then a pitch soaked, lit brand came guttering through the air to land a few paces away. Jon snatched it up before it could be smothered in the snow.

'Give us a few minutes,' he called to the others. He jerked his head at Gendry, indicating he should follow, before moving into the tunnel to their left, torch held high. He looked around, scanning the walls for irregularities, indications of life, anything really.

'What are you looking for?' Gendry asked, following closely behind him.

'I don't know,' Jon admitted. 'A long shot really. Just something Y- someone - once told me about the tunnels out here.' They walked for a few more minutes, Jon still scanning the walls and roof anxiously, before he sighed, stopping abruptly. Gendry wasn't expecting it and crashed full into his back, reaching out to steady himself by grabbing Jon's arm and hip. He hissed in pain as he did so. Jon turned around.

'Are you alright? You said something to Berric about your arm?' Gendry waved him off, teeth gritted.

'It's fine. We have bigger problems right now.' Jon frowned but let it go.

'You didn't find what you're looking for?' Gendry asked.

'No,' Jon muttered. 'I want to try in the other direction as well if you're up for it?' Gendry jerked a quick nod, steady blue eyes meeting his. Jon felt a bit better that even if he was in a shit of a situation, he wasn't alone. And Gendry was a hell of a rock to have at your back in a bad situation.

They trudged back the way they had come, the only sounds the hiss and splutter of their torch and the crunch of the rocks of the cave floor under their feet.

They reached the hole in the roof again, the tunnel gradually lightening as they approached it. Jon barely spared a glance for the other men, still peering down in at them before he crossed over into the right hand tunnel. He repeated the process for several more minutes, scanning the cave walls, before he let out a happy sound, shoulders slumping in relief.

Gendry came around beside him, marvelling at what was shown in the flickering light of the torch.

'It's like the ones at Dragonstone,' he murmured, reaching out to touch the large, white figures painted on to the wall of the cave.

'The Children of the Forest,' Jon agreed. 'All of Westeros was their lands before the Andals and the First Men came. They used tunnels like this one to travel huge distances. This will lead us out eventually. C'mon. Let's tell the others.'

Jon and Gendry walked side by side back to the hole. 'This tunnel's basically an ancient highway,' Jon relayed up to the others. 'Gendry and I can follow it North until it comes back to the surface. We can regroup and meet you at the Fist of the First Men. If we're not there in 5 days, keep with the mission and we'll meet you back beyond the wall.' Gendry looked at Jon, startled, but Jon gave him a reassuring half smile.

'I know these lands,' he murmured. 'I almost was a wildling, for a time.' His smile turned sad and a little bitter. Gendry assessed him, eyes glancing over his, testing his resolve. He'd not known Jon Snow very long, in the scheme of things, but there was something solid and honest and earnest about him. Gendry knew Jon would get them out, or die trying. He smiled crookedly and sketched a mock bow.

'Lead on m'lord.'

Berric tried to argue that the rest of the group should find a way into the cave to continue together but Jon waved him off.

'It's too risky. Gendry and I were lucky not to break our necks. Chuck us down a couple more torches and a bit more food. You'll all have more chance of hunting up there than we will down here.' Berric frowned but obeyed and shortly a number of small parcels came thudding down into the snow. Gendry and Jon both set about stuffing things into their packs, Gendry now noticeably slower.

'You lot head off,' Jon called. 'Make the most of the light while you have it. I'm going to tend to Gendry's arm and then we'll start moving too.'

'Good luck lad,' Berric called.

'May the Lord of Light be with you,' Thoros added. With no more fanfare than that they pulled back from the edge and disappeared.

Jon turned to Gendry, meeting dark, steady eyes. 'Well,' he said. 'It's just you and me now.'

Gendry grinned back at him. 'I was getting sick of Jorah's moping anyway.'