Rubbernecker

n. (1) an overly inquisitive person; (2) a tourist (esp. one on a guided tour).

To rubberneck:
vi. (1) To look about or survey with unsophisticated wonderment or curiosity; (2) go on tour (sightsee)

From the movie Secret Window starring Johnny Depp:

Ted: Maybe I should take a walk around the block.
Amy: Yes, that'd be good.
Mort (Depp): Aw heck, Ted, live a little - make it two. Rubbernecker.