Creating a very detailed open world city map

Thanks for your answer. We really appreciate it.

To be more clear we are developing an open world metaverse. So right now we are trying to import a city map with only the land parcels, roads and landscapes (no buildings). Furthermore, we are trying to develop a builder tool using which a player can develop his own 3d digital building on a land parcel located in the city using 3d modular assets from our library.

Every digital asset created by the players would be stored on the blockchain

Are there any suggestions from you side regarding how to implement those features?

It would be very helpful
Thanks