If you have access to a freezer, that would be even better. Pump and store your milk in the storage bags and freeze them asap. When I traveled to Europe several years ago, that's what I did. I was lucky enough to be able to use our office's freezer for my milk. I stored my milk there until it was time to leave. I then packed the frozen bags (probably 12-15) in a soft sided cooler with ice packs in my checked luggage. When I arrived back at home after about 15 house of traveling, much of the milk was still frozen. Good luck!