Gandhinagar comprises thirty sectors. It is a highly-structured city and has a highly ordered street grid - comprising blocks that are divided by two types of streets, similar to US avenues and streets. Gandhinagar has "letter roads" (CH, CHH, JA) and "number roads" (1,2,3). The letter roads run parallel across the city perpendicular to the number roads. The number and letter roads intersect each other forming a grid; each block or square in the grid is given a sector number. Each intersection is marked by signal names such as CH1, CH2, CH3 or JA1,JA2.