nerve center

a thing or place that is of greatest importance to an activity or interest Wall Street's undisputed status as the nerve center for the world of high finance Synonyms axis, base, capital, central, core, cynosure, epicenter, eye, focus, ground zero, heart, hub, locus, mecca, navel, center, nexus, nucleus, omphalos, seatRelated Words headquarters; happy hunting ground, hive, hotbed, hot spot, playground, playland; kernel, nub, pith; deep, thick; essence, quintessence, soul; attraction, lodestone (also loadstone), magnet, polestar