Fun fact! There are lots of secret chest in Mondstadt! Like on top of this building, there is about two or three + a teleport waypoint to open! Honestly there are tons
How to get the secret Luxurious Chest in Mondstadt in Genshin Impact - Gamepur
Mondstadt Region Puzzles, Secrets, and Hidden Chests | Genshin Impact - GameA
Mondstadt Region Puzzles, Secrets, and Hidden Chests | Genshin Impact - GameA
All secret/ hidden chests for the Mondstadt Achievement [Full Guides] Genshin Impact | HoYoLAB