Does anyone know of a good, masculine messenger bag?

I’m going to university in the fall, and I want something that isn’t too feminine or looks like a purse. I’m looking for something leather or canvas. I also really like “Indiana Jones-ish” kinds of bags. But there are so many bags that have a lot of clasps and zippers in the front, but it’s just too much. I prefer simple on the outside, and then open the flap and boom, it’s all organized lol.