 The first road was built in Harrison County in 1809 connecting Corydon with Mauckport on the Ohio River . A tow @-@ and @-@ ferry line was operated there by the Mauck family bringing settlers into the county from Kentucky . This road and ferry greatly expanded the county 's economic viability and ease of access to the outside world , leading to a rapid settlement of the area . The county 's population more than doubled in the following decade . 
