There are plenty.

Ironically, building a medieval cathedral is one of those analogues. Yes, we can build a cathedral with modern equipment, but we don't know how much of it was done without it. Much of the knowledge was considered too commonplace to be worth writing down.

A modern one ... how about a Saturn V rocket. We no longer have the steel mills with big enough tooling in order to actually build such a mammoth beast. We would have to reinvent much of that tooling in order to do it again.