when the US Constitution was adopted?

United States Constitution was adopted on September 17, 1787 in Philadelphia Constitutional Convention, in which was attended by 55 delegates (on a regular basis in the meetings was attended by about 30 people), representing 12 states, as Rhode Island refused to participate in its work. The aim of the Constitution was the legal registration of the new nation - the United States of America. The Constitution came into force on March 4, 1789 after ratification by the requisite majority of states.
the adoption date of the US Constitution