Before construction on the I&M Canal began, canal commissioners encouraged early settlers to move to the region and from communities. The end of the Black Hawk War brought a flood of adventures and speculators to the western frontier and, soon, land fever spread throughout the region.
Small towns, especially those situated on the banks of rivers, were laid out and fledgling enterprises along those marine routes were started.
The towns of Chicago and Ottawa were platted by the canal commissioners in 1830 to serve as both the gateway to the I&M Canal via the Chicago River and the western terminus on the Illinois River. By 1836, canal commissioners made the decision to locate the western terminus farther west, and the town of LaSalle was platted in 1838.
With fertile farmland and access to large-scale grain terminals in Chicago, towns and communities lay out along the I&M Canal, especially those in LaSalle County where grain facilities were numerous. Once the I&M Canal opened, the population of the county increased, and the town of LaSalle, with its steamboat basin, became a place of tremendous activity.
Grain elevators and warehouses lined the banks of the canal and river towns in Illinois in the 19th century.
The flow of grain was primarily from west to east along the I&M Canal and the railroads. Soon after the opening of the canal, facilities for storing and forwarding the products were established along the route.
In the early 1860s, John Armour, a prominent businessman in Ottawa, constructed a grain warehouse along the north bank of the I&M Canal overlooking downtown Seneca. Rising four stories above its limestone foundation, the 65-foot-tall grain warehouse represents the oldest frame elevator still standing along the canal.
Today, the structure is known as the Seneca Grain Elevator, and in 1997, the building (Armour’s Warehouse) was added to the National Register of Historic Places.