I think the best bet might be a large number of fired clay tablets, probably with other languages to help provide a guide to recreating the text in the future (

I think the best bet might be a large number of fired clay tablets, probably with other languages to help provide a guide to recreating the text in the future (rosetta stone). You'd want to store them in places that are dry, and not prone to flooding. Caves seem like a decent option (dead sea scrolls) though ideally you'd cover a large geographic range for redundancy. The 10,000 year clock project might have some useful ideas for you. Though buying a mountain in the desert, then drilling a hole in it is only possible with privilege and obscurity. https://longnow.org/ideas/02017/06/07/how-can-we-create-a-manual-for-civilization/ https://longnow.org/ideas/02017/06/07/how-can-we-create-a-ma... Scroll to the section "Projects that inspired the Manual For Civilization:" https://longnow.org/store/proto-1-drawings-pbk/ https://longnow.org/store/proto-1-drawings-pbk/ "Long Now has compiled a record of all of the drawings made to create Prototype 1 of the 10,000 Year Clock into a new self published book. Geared towards the mechanically inclined, this book is a highly technical document of manufacturing specifications. It also includes several math notebooks and spreadsheets that Danny Hillis used to make the underlying calculations for parts of the Clock. Long Now hopes that the widespread distribution of these plans will ensure that the knowledge and work that went into building our first Clock prototype is not lost and that this will help the survival of the Clock itself and the long-term thinking it represents."