The Legend of Zelda: Breath of the Wild’s "From the Ground Up" side quest begins just behind Myham Agana shrine in Hateno Village. You’ll find a group of construction workers there: Bolson, Karson and Hudson. Speak to them, and you’ll eventually unlock two quests. Purchase the house as part of the "Hylian Homeowner" side quest, and Hudson will leave on a mission to create a town from the ground up (GET IT?).
"From the Ground Up" is a long and winding quest that follows the construction of Tarrey Town from nothing to … well, if not a metropolis, as bustling a city as you’ll find in Hyrule. In this guide, we’ll show you how to do it all — including the characters scattered throughout the world.
From the Ground Up part 1: Akkala Tower region
Travel to the island in the middle of Lake Akkala. It’s in northeastern Hyrule, within the Akkala Tower region, and Dahj Hesho shrine is the closest warp point.
Speak to Hudson, and he’ll ask you to collect 10 bundles of wood. There are plenty of trees on the island at this point, so cut them down and speak to Hudson again.
(Also, while you’re area, make sure to visit the Great Fairy Shrine.)
From the Ground Up part 2: The Southern Mine
Now Hudson needs a Goron with a name ending in "son," because why not? You’ll find Grayson sitting near a fire and a cooking pot in the Southern Mine, on the path that leads up Death Mountain to Goron Village.
Speak to Grayson, convince him to head to Hudson, and return to Tarrey Town, where you can now access a gem shop.
From the Ground Up part 3: Kara Kara Bazaar
The next time you speak to Hudson, he’ll need 20 bundles of wood … which is probably getting annoying at this point. But those are table stakes in "From the Ground Up," so keep cutting down trees and stockpiling wood as you find it.
Give them to Hudson, and he’ll tell you about a tailor he needs. (He’s building a town, so it makes sense.) You’ll find the woman in question in Kara Kara Bazaar, which is northeast of Gerudo Town and Daqo Chisay shrine.
Speak to Rhondson, convince her to move to Tarrey Town, and return there, too. She’ll open a shop and sell you the Desert Voe armor set, which protects you from the extreme heat of the desert.
From the Ground Up part 4: Rito Village
Speak to Hudson again, gather 30 bundles of wood, speak to him again, and he’ll tell you he’s looking for a merchant.
Travel to Rito Village (Akh Va’quot shrine is closest), and speak to Fyson. Convince him to move, return to Tarrey Town, and he’ll have opened a general store specializing in arrows.
From the Ground Up part 5: Zora’s Domain
Speak to Hudson again, gather 50 bundles of wood (ugh), speak to him again, and he’ll tell you he’s looking to get married. He just needs someone to officiate.
Travel to Zora’s Domain, and speak to Kapson. (He’s hanging out in the area above Ne’ez Yohma shrine.) Convince him to move, return to Tarrey Town, and you’ll find Hudson at Rhondson’s clothing store.
From the Ground Up part 6: Hateno Village
Speak to Hudson again (this time at the clothing store), and you’ll learn that he needs wedding guests. Warp to Myham Agana shrine in Hateno Village, walk to your house, and speak to the two construction workers you met way back at the beginning of the quest — Bolson and Karson. Invite them to the wedding, and return to Tarrey Town one more time.
From the Ground Up part 7: A Tarrey Town wedding
When you arrive in Tarrey Town, the wedding ceremony will begin. Speak to Hudson after he’s a married man, and you’ll receive three diamonds for your hard work.
Not only have you been instrumental in helping create a Hylian city, but you also have access to an inn where you can stay free of charge. (Look for Kapson the Ruto to find it.)
Tarrey Town bonus: Granté and the hidden shop
On top of a building in Tarrey Town, you’ll find Granté, who runs a secret shop. (See the gallery above for exact positioning.) Here, you can purchase a bunch of high-level gear — including the Hylian Shield if you ever lose it. None of the merchandise is cheap, but it’s all good stuff.