Its construction for the World 's Fair of 1889 was an astounding engineering achievement ' 18,000 pieces joined together by 2,500,000 rivets , soaring 300 m ( 984 ft ) into the air but standing on a base that is only 130 m ( 1,400 ft ) square .
Its construction was for the World 's Fair of 2002 , and was a small engineering feat .