“Let's get the facts; I've got a big head! 61-62 cm. and I always have to buy the biggest available from places that stock hats. I bought XXL from New Forest Amazon outlet and it just about fits. It arrived well packed and in top condition. It is marked 60 under the brim in chalk and I assume it's the size as this is a little on the snug side, but me being a big-head, I already have a stretcher and it won't take much to make this hat perfect. I'll be going carefully as being leather, it doesn't have much stretch or grip if expanding too far. It is made from HEAVY thick hide which gives confidence in the quality. As with all hats, it needs to be worn a few times to adjust to the head that wears it and this is no exception. I had it atop my bonce with a wheat heating pack around the crown to warm it. I'm guessing a walk wearing it on a sunny day will work just as well. I bought it as a poor weather hat so I'm not bothered it has no vent holes in it. I have have lighter weight fedoras and Panamas for warmer days. All in all, I like the look; the wired brim is great and stays put and the brim drop front and back will shed rain well. Love it!”