I have a 6' keyed cable lock from Home Depot. I tour in the U. S. I lock my bike up whenever I go into a restaurant or store where I'll be out of sight for awhile. At night I lock it to a tree or the picnic table, as close to my tent as possible, in hopes that I'd hear if someone was tampering with it. (Then what would I do?) I think a serious thief could still get my bike, but I want to discourage them as much as possible. I also want to discourage someone from walking by, seeing a nice, unlocked bike with interesting bags on it, and riding away - unplanned but just as despicable.