Cultural - adjective
1. of or pertaining to culture or cultivation.
Institution - noun
1. an organisation, establishment, foundation, society, or the like, devoted to the promotion of a particular cause or program, esp. one of a public , educational, or charitable character: This college is the best institution of its kind.
2. the building devoted to such work.
Cultural Institutions are elements within a culture/sub-culture that are perceived to be important to, or traditionally valued among, its members for their own identity.
Sources: http://dictionary.com; http://en.wikipedia.org/wiki/Cultural_institutions