The first steamboat from the Mississippi made the passage up Rock River, passing the rapids and stopping at Janesville.

The evidence

• “In June, 1836, tho first steamboat from the Mississippi made the passage up Rock river. This was an "event" to the settlers along the river, and availing themselves of the opportunity of a steamboat ride, it was found by the time she arrived at Wisconsin City her decks were pretty well crowded with passengers; but "rounding to" at East Wisconsin City, she took on Dr.”

  1856-history-of-rock-county/24-rock.md, PDF p. 162 / book p. 146

  Guernsey, Orrin, and Josiah F. Willard, editors. History of Rock County, and Transactions of the Rock County Agricultural Society and Mechanics' Institute. Janesville, Wis.: William M. Doty & Brother, 1856. Cornell University Library via the Internet Archive, archive.org/details/cu31924028871593.

  Grade A: Found on a page of one of our sources