The plan specified that most streets would be laid out in a grid. To form the grid, some streets (later named for letters of the alphabet) would travel in an east-west direction, while others (named for numbers) would travel in a north-south direction. Diagonal broader avenues, later named after the states of the Union, crossed the north/south-east/west grid. The diagonal avenues intersected with the north-south and east-west streets at circles and rectangular plazas that would later honor notable Americans and provide open space.