Manhattan is the commercial, financial, and cultural center of the United States. Manhattan has many famous landmarks, tourist attractions, museums, and universities. It is also home to the headquarters of the United Nations. Manhattan has the largest central business district in the United States is the home to the largest number of corporate headquarters in the nation. It is indisputably the center of New York City and the New York metropolitan region, holding the seat of city government, and the largest fraction of employment, business, and recreational activities.

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Wikipedia - Manhattan