Illinois became the 21st state to enter the Union on December 3, 1818. It was discovered in 1673 by explorer Louis Jolliet and Jesuit Father Jacques Marquette when they floated down the great Mississippi, returning up the Illinois River and crossed the portage to Lake Michigan where Chicago now stands.

Our state is located at the heart of the great interior river system of the continent. The Mississippi, Ohio and Wabash rivers form its western, southern and eastern boundaries. Across it flows the Illinois, the Kaskaskia, the Sangamon, the Spoon, the Rock, the Embarrass, the Kankakee and the Des Plaines – each, in its day, a highway of trade. Illinois is a level land of fertile prairies and numerous groves. Beneath its surface are deposits of lead, vast beds of bituminous coal and known and unknown pools of oil.

Illinois’ land area and water areas are approximately 58,000 miles. Illinois measures 385 miles long and 218 miles wide. The highest point is 1,241 feet located at Charles Mound in Jo Daviess County and the lowest point is 268.58 feet located at Cairo on the Ohio River.

In Illinois, the Governor, one of six elected constitutional officers, heads the Executive Branch. The General Assembly, a bicameral body made up of the 59-member Senate and 118-member House of Representatives, heads the Legislative Branch. The seven member State Supreme Court heads the Judicial Branch.

Three levels of local government exist in Illinois – County (102 in the state), Township (84 counties have them), and Municipal (1,274).

The third branch of State Government is made up of the State Supreme Court, five Appellate Courts with 34 judges, and 22 Circuit courts, with at least one circuit judge from each county. More Than 400 judges and 350 associate judges handle cases.

Illinois has 20 votes in the Electoral College, which is determined by the number of United States Senators and Representatives in Congress from Illinois.


Since entering the Union as the twenty-first state on December 3, 1818, Illinois has had six state capitol buildings in three cities. The first Capitol was located in Kaskaskia. It was a simple, two-story brick structure, which rented for $4.00 a day. The 29 members of the House of Representatives met on the first floor while the state’s 14 senators met in the chamber directly above.

In 1820, Vandalia became the site of the second State Capitol. This building, the first capitol built by state taxpayers, was a plain, two-story frame structure. After being destroyed by fire, a new capitol was built in 1824 for $15,000.

Shortly after it was completed, citizens campaigned to move the Capitol near the geographical center of the state. In 1833, the General Assembly passed an act enabling votes to choose between Vandalia, Jacksonville, Peoria, Springfield or Alton.

Vandalia residents were alarmed at the mood of the assembly and were determined to retain the capitol. In 1836, without authorization and while the legislature was recessed, they tore down the capitol and replaced it with a brick Statehouse costing $16,000.

Despite this, Springfield was named the third Capitol, and the state’s fifth Capitol was built in 1853 at a cost of $260,000.

The sixth and present State Capitol was completed in 1888 in Springfield. It was designed by architects John Cochrane, George Garnsey and Alfred Piquenard. The Capitol is situated on a nine-acre plot and is in the form of a Latin cross. The dome is supported by circular foundation, 92 feet in diameter, set on solid rock 25 feet below the grade line. The height from the ground line to the top of the dome is 361 feet and 405 feet to the tip of the flagstaff.

A restoration of the dome’s interior in 1986 is believed to be the first since the Capitol’s completion. All surfaces were cleaned and repainted, and the entire dome was illuminated. The renovation cost $1.3 million.