do you call?

so, here is the situation.
I traveled across the pond to the west coast for an interview. The time on land between flights was three days. I met up with two friends for dinner the first two days. The girl friend of a good buddy lives in that town; she is also a classmate from last year. Even though I might not have the best relationship with her, do I call and maybe hang out the last night there? Or, do I go to an alum event, and make some contacts? Or, after a full day of interviews, sit and relax?

What's your take?