Search teams in Tenerife are still scouring the Spanish island for missing British teenager Jay Slater.
The 19-year-old, from Oswaldtwistle in Lancashire, vanished without a trace while on holiday last Monday.
Police hoping to track him on Sunday focused on some small outbuildings in a village at the bottom of a ravine, near to where his phone was last traced to.
Mr Slater has not been heard from since calling one of the friends he had travelled with eight days ago – telling her he was lost, his phone was running out of battery and he needed water.
Specialist dog teams have also been out looking for him, with much of the search focusing on an area near a national park in north-western Tenerife.
The teams are working in challenging conditions at Rural de Teno National Park – Mr Slater’s last known location.
Officers from the Guardia Civil in the Canary island were spotted searching two structures at the bottom of a ravine in the park on Sunday.
Efforts appeared to be primarily focused on the one area after days of searches in the nearby village of Masca and the surrounding landscape.
One man who had flown out from the UK to help described his role in the search operation through ravines as like “looking for a needle in a haystack”.
Mountaineer Paul Arnott, 29, of Flitwick, Bedfordshire, said: “You cannot believe how steep and big an area it is until you get out here.
“I thought there would be more people searching, though.”
Mr Slater’s friends and family have said he had earlier left the group he travelled with in the tourist hotspot of Playa de las Americas, on the south of the island.
After leaving the NRG music festival at Papagayo night club, the apprentice bricklayer got in a car with two men he had met to drive to the national park in north-west Tenerife.
Lancashire Police said last week it had offered to assist Spanish police searching for him, but were told their counterparts in Tenerife felt they had enough resources.
Mr Slater was on his first holiday without family and had travelled to attend the festival with two friends.
One of them, Lucy Law, is thought to have been the last person to speak to him, said he told her over the phone he had missed a bus and decided to walk the 10-hour journey home but was lost, needed water and only had 1% battery left.
A fundraising page set up by Ms Law to help find him has gathered more than £30,000 worth of donations.
The Rural de Teno Park is about a 40-minute drive from where Mr Slater and his friends were staying.
A remote and wild national park, it is a world away from Los Cristianos and Playa de las Americas, the party town holiday resorts of the island’s south coast.
Deep ravines and huge daunting mountains make the national park a difficult place for the Spanish search teams to navigate.