Does iPhone lock code also protect the sim?

Probably a stupid question but I'm not very "tech savy"
Left my iphone at a friend of a friends and although it had a passcode on it, I'm worried that they'll be able to remove the sim and look through my stuff on their phone (… Long story… ) … Seeing as I had a passcode on the phone, would this protect my sim if they tried it in their phone?
And I can't just run around and get it because I'm 60 miles away just now urch.

No. The content of your iPhone is safe. None of that content is on the sim card. Worst that could happen is that someone could use your sim card in another iPhone and make calls with it possibly using up your minutes or calling Japan or something and racking up a fat phone bill. Best to report your phone as lost or stolen until you retrieve it. Then you can call and let your carrier know it's back in your possession.