Five pubs in nine & half hours? I suppose fifty is quite a big party to be dragging around to multiple pubs & clubs.
As I've probably told you before: I remember for one of my pals twenty-first birthdays we attempted, with a party of maybe a dozen or more people, to do twenty-one pubs. If you work it out, it's actually quite hard to get round twenty-one establishments (this was purely pubs, mind; it didn't stretch into the early hours with a club or anything) in an afternoon & evening; once you take into account ordering drinks, drinking them, & getting to the next pub, especially as the night wore on. We did manage it though.