Is it worth traveling to Cognac region? Is there anything to do beside touring distilleries?
The cathedral at Poitiers will knock your socks off.
The towers and harbor at La Rochell are interesting as all get out. I've never seen anything quite like the Marais Poitevin anywhere else in europe. There's a bunch of Roman stuff at Saintes. The ramparts at Angouleme are well-preserved. The royal rope factory at Rochefort is nifty if you like royal ropes; my wife didn't care for it too much, but she doesn't appreciate the really good stuff.
Not really that much there. You can pretty well see most of the area in a month.