Travelers Cheques

I'm off in August and I'm going to take a couple of hundred quid in lira cash and a couple of hundred sterling cash, and the rest in sterling travelers cheques. Now call me thick but when I get to Icmeler will I be able to exchange the sterling travs into liras or can I only exchange for sterling. Would I be charged commision as you are here when you by sterling travs. Any advice most welcome. 
