An Ancient Furnace is a high-tech Furnace that holds a Blue Flame found in Breath of the Wild. There are two of them found throughout Hyrule, one in Hateno Village near the Hateno Ancient Tech Lab, and another in Deep Akkala, near the Akkala Ancient Tech Lab.
- Main article: Locked Mementos
As part of the Locked Mementos main quest, Link will need to use the Ancient Furnace in Hateno Village to carry a blue flame up to the Hateno Ancient Tech Lab. Purah will instruct Link that he needs to light the furnace outside of the tech lab in order to restore power to the Guidance Stone inside. The Ancient Furnace is visible from just outside the tech lab, located behind Reede's house. Purah will suggest that Link use a Torch to carry the flame.
Link can walk right up to the Ancient Furnace and swing his Torch or other flammable weapon to light it on fire. Link can either travel through the main part of Hateno Village, or around the Zelkoa Pond to the north. In both directions, there are village lanterns that Link can light up along his way. Once Link arrives at the Hateno Tech Lab, he can light the furnace outside, which will in turn power up the Guidance Stone inside.
Carrying the Blue Flame.
- ↑ All right, then. First I need you to run an errand for me. ... What's with that look on your face? You didn't think I'd fix your Sheikah Slate for free, did you? Hmmm... Post Slumber of Restoration, subject is plagued by...presumptuous... tendencies. Noted! Let me explain what this errand entails. You know the unlit furnace on the wall just outside this laboratory? Could you please bring the blue flame from the ancient furnace in town? Oh, and also use it to light our furnace? This sweet little Guidance Stone will start working once you do that, allowing us to restore your missing runes! - Purah
- ↑ You'll find the ancient furnace on the high ground behind Reede's house. As soon as you leave this laboratory, head left until you're at the cliff's edge. Then make use of your scope! You'll see a blue flame. That's the ancient furnace. - Purah
- ↑ When bringing back the blue flame from the ancient furnace, you may find it helpful to use a torch. There should be one at the entrance of this house. Feel free to use it. - Purah
- ↑ Blue flame makes it sound fancy, but it's really just the same as a regular flame. If it gets wet, that's that. It'll help to light the village lanterns you'll see on your way back here and to avoid steep inclines. - Purah