So, how do I get it out?

Yes. Lots and lots of water for the corpse and a good strong knife.

Is there somewhere suitable in your garden where you can plant the fig tree into the ground? Don't bother trying to get it out of the pot just bury the lot. The remains of the pot will restrain the roots.

Our fig tree started life in an old tin bath then we planted it in a south west facing border (bath and all) The roots are well and truly through the bottom now but the sides of the bath keep everything under control.

Can you get the big terracotta pot safely onto the floor? If possible get the compost very wet and use an old carving knife to saw the bits of root off and it should loosen.
Easy does it though.
I am a great fan of my mothers old carving knife for separating plants.

Fig trees need root restraint. It will do no harm to chop off those roots that are through the bottom of the pot. Treat it mean, don't put it into too big a pot or the open garden. Figs in open ground get huge and do not fruit as well. The figs on our two trees are more advanced than I have ever seen before.

Thanks for the replies.

Yes, Alima I had thought that a good soaking might be of help, I would really hate to lose the pot, it has aged beautifully, moss on it etc.

I also have a bit of a problem with a fig tree in a pot, went to move it with a view to re-potting, and found it had broken through the bottom of the plastic pot it is in and rooted into the ground!

Sure his mind is not on other things?

Anyway, back to Walter. How about chopping back everything above ground then painstakingly hand-forking out the compost, roots, etc. Make the compost wet to make it easier? I have used an old pallet knife before now to slide round the sides between compost and pot. Good luck.

Patience is your best tool, along with a builder trowel if you have one. Just take your time and remove a little soil at a time. I have the same problem with a couple I have that are urn shaped.