The Place To Be Meaning

(idiomatic) A great, trendy, or perfectly suitable place

Example: 2011, Sarah Parr, Cal Poly 2012
  The UU is a great place to be on campus to socialize but when business needs to be taken care of the five story library is the place to be!
1977, Paul Elliott Rock, Drugs and Politics
  Indeed, one of the problems of deviant communities in San Francisco is coping with the periodic influx of a new generation of bohemians who have heard that it is the place to be: the beatnik migration of the late fifties and the hippie hordes of 1967.