In the episode 7 of Friends, we find the following talk:
Rachel: I just never had a relationship with that kind of passion, you know, where you have to have somebody right there, in the middle of a theme park.
Ross: Well, it was the only thing to do there that didn’t have a line.
Rachel: There, well, see? Barry wouldn’t even kiss me on a miniature golf course.
I checked several meanings to the word "line" in some dictionaries but I could not find that appropriate one. I think that "to have a line" isn't an expression. I didn't know what Ross meant. Could someone help me, please? Thanks in advance!