The Third LaSalle County Courthouse at Ottawa, completed in the latter part of 1841 on the site of an earlier courthouse, was a two-story brick Greek Revival building with imposing columns at the south end and a cupola capped by a weather vane. A grand improvement over earlier log courthouses, it became a center of both legal and social activity during the height of the canal period. After the Illinois State Constitution of 1848 established three grand divisions of the Illinois Supreme Court and placed the Northern Division at Ottawa, the Supreme Court met in the LaSalle County Courthouse until a separate Supreme Court building was completed in 1860. Abraham Lincoln practiced law there as a frontier lawyer, arguing a case before the Supreme Court in Ottawa beginning June 11, 1851, and lasting six days, returning on December 3, 1852, as an Illinois-Michigan Canal Commissioner to hear claims against canal construction, and making his final appearance there on the night of the first Lincoln-Douglas Debate, August 21, 1858, during a rally organized by prominent local Republicans. The courthouse was destroyed in the Great Ottawa Fire of 1881 and replaced with the present courthouse.
