The district is divided into four quadrants of unequal area: Northwest (NW), Northeast (NE), Southeast (SE), and Southwest (SW). The axes bounding the quadrants radiate from the U.S. Capitol building. All road names include the quadrant abbreviation to indicate their location and house numbers generally correspond with the number of blocks away from the Capitol. Most streets are set out in a grid pattern with east–west streets named with letters (e.g., C Street SW), north–south streets with numbers (e.g., 4th Street NW), and diagonal avenues, many of which are named after states.