This page offers a walkthrough on how to reach the Hateno Ancient Tech Lab from Kakariko Village during the Locked Momentos quest. This page includes the best route to follow in order to find gear and areas of interest.
Main Quest: Locked Mementos
The Dueling Peaks Stable and Kakariko Bridge mark the fork in the road at which you can turn east instead of north to head out into the far eastern region of Hyrule and seek out Hateno Village.
The easiest way to get there is to fast travel to the Ha Dahamar Shrine. If you haven’t completed the shrine yet, it doesn’t take very long to get to the fork by foot or horse.
You will eventually arrive at a Guardian graveyard along with a tall, imposing wall. This is Fort Hateno, a major landmark that marks the divide between areas ruined by Calamity Ganon and the remote settlements of the east that did not suffer as much damage. Feel free to scavenge the Guardians for their parts, as there are a lot of them, but beware the one Guardian furthest to the left that is still awake.
Beyond the fort is a sprawling wilderness. To immediate right is a cooking pot and a campfire, so use this as a chance to replenish supplies and take a rest if you need to. There are also several honeycombs that you can harvest. Use a Bomb to kill the bees first though, or they will attack you.
The road will fork but both take you to the village. The south fork will let you pass by the Hateno Tower, this region’s tower, so this is the way we are going. It is surrounded by Bokoblins and Moblins so approach carefully if you choose to do so. The Tower itself is covered in thorns so climb carefully around them. You can also set them on fire if you want to and use the Paraglider to catch the updraft and climb less.
Keep following the winding path straight and you will enter Hateno Village. There are multiple ways to enter the village. If you get stopped by a guard, they will eventually let you through. The NPCs you chat with will be more than happy to point you in the right direction to get to the lab. It is located in the outskirts of the village on a hill. There are also various shops to check out, including one shop where you can dye your armor different colors.
The Hateno Ancient Tech Lab that we are looking for is outside of the village, so make your way through all the business and you will find a long, winding path that takes you to a cape overlooking the Hateno Beach. The building at the very top of the cape is the lab. The path is marked by a bunch of curious lanterns so just follow them.