I got a question for you: Pioneers to the area first called "Town of Lake" were S.S. Crocker and John Caffrey. Indeed, Crocker earned the nickname "Father of the Town of Lake." By February 1865 the area was incorporated officially as "Town of Lake" the area still consisted of fewer than 700 persons. In the early 1860s the meat packing industry of the United States was still located in Cincinnati, Ohio, the original "Porkopolis" of the pre-Civil War era. However, with the end of the American Civil War, the meat packing industry had started to move westward along with the westward migration of the population of the United States. For the meat packing industry moving west meant coming to Chicago. As early as 1827, Archibauld Clybourn had established himself as a butcher in a log slaughter house on the north branch of the Chicago River and supplied most to the garrison of Fort Dearborn. Other small butchers came later. In 1848, the Bull's Head Stockyard began operations at Madison Street and Ogden Avenue on the West Side of Chicago. Operations for this early stockyard, however, still meant holding and feeding cattle and hogs in transit to meat packing plants further east -- Indianapolis and, of course, Cincinnati.

Based on this passage, which city was known as porkopolis after its slaughterhouse district?
Let's think first:
To answer the question, consider the following: In the early 1860s the meat packing industry of the United States was still located in Cincinnati, Ohio, the original "Porkopolis" of the pre-Civil War era.
Therefore, the answer is Cincinnati , Ohio.