What are good events/places to go to in NY state area for 21st birthday?

So my fiance is turning 21 in a few days. We are planning on going somewhere for the weekend next weekend to celebrate. We are both from California so I am used to Vegas and I went to Reno for my 21st. We are willing to travel anywhere within decent range such as NYC, Boston, ect. But can anyone suggest something that would actually be really cool for a 21st bday in the east coast? He will be drinking and he wants to go to a casino but Ive been told that they aren't really common here? I want to give my Fiance the best 21st bday that he could ever hope for :) ideas???