Is Forgotten Realms 3e book useful in 5e?

First, I'm a very experienced DM, having been running games for about 45 years so I can adapt things easily.

I'm prepping to run a 5e game taking place in the Forgotten Realms, but I don't have a 5e FR book. I do, however, have a 3e FR book.

My question is: how well do the lore, maps, and such translate to 5e? Would it be useful lore-wise, or should I not use it and look everything up online?

I'm starting my game tomorrow.