Fire crews say they are struggling to extinguish a blaze on Ilkley Moor as they spend a fifth day at the scene.
The smoke can be seen from about 10 miles away at Yeadon Banks
Visibility is limited as smoke from the fire, which has already destroyed about 500 acres of moorland, is smothering around three square miles of land.
Three crews are tackling the flames, but as soon as they put them out in one area they re-ignite elsewhere.
A fire service spokesman said the fire was contained, but did not know when it would be extinguished completely.
Mark Whittaker from the fire service said the main concern had been to stop the fire spreading into Ilkley.
"There's been a lack of water and obviously with the dry conditions over the summer that we've had we're struggling to put it out," he said.
"The wind keeps getting up and dropping down and it's that that's a bit of a nightmare."
Conservationists say it could take up to 20 years for the moors to recover from the damage caused so far.
Smoke from the blaze can be seen for miles around and many walkers are still going on to the moors to see the extent of the damage for themselves.
One of the walkers, Mike Jarvis, said that in parts of the popular beauty spot there was just nothing left.
"It's burnt off all the bracken, all the ground cover, everything has burnt off down to the soil," he said. "It looks almost like a war zone."