The Julian M. Carroll Purchase Parkway is a controlled-access highway running from Fulton, Kentucky to Calvert City, Kentucky, near Kentucky Dam, for a length of 52 miles (84 kilometres). It begins at the Tennessee State Line concurrent with US 51 only a few yards (metres) from an intersection with US 45W, US 45E, and US 45 at its western terminus, and US 62 just north of Interstate 24 at its eastern terminus. It is one of nine highways that are part of the Kentucky parkway system.

The parkway passes the cities of Mayfield and Benton, Kentucky.

Federal legislation designated the entire length of the Purchase Parkway as Interstate 69 in 2002. On June 6, 2008, President George W. Bush signed HR-1195 (SAFETEA-LU Technical Corrections Act of 2008), reaffirming the I-69 designation for the Purchase Parkway and further authorizing Kentucky to sign the route as such with Federal Highway Administration (FHWA) approval. The Kentucky Transportation Cabinet had planned I-69 signs on the parkway during the summer of 2008, but the FHWA is requiring the KYTC to either upgrade substandard portions of the route or obtain a design waiver before can be signed as I-69. at present, the KYTC plans to wait until Tennessee completes its portion of I-69 before seeking approval to sign the Purchase Parkway as I-69.

Originally named Purchase Parkway for the Jackson Purchase area it diagonally traverses, the road was renamed for Julian M. Carroll, a former Kentucky governor from McCracken County, in 2001. The Purchase Parkway carries the unsigned designation of Kentucky Route 9003 (JC 9003). The Mayfield Bypass, which was incoporated into the parkway following its construction, is also signed as US-45 Bypass. It will eventually carry the signed designation of Interstate 69 from I-24 to the Tennessee state line.

Completed in 1966, the parkway incorporates a pre-existing four-lane divided bypass around Mayfield. This section of the parkway is also designated as US 45 Bypass.

Except for the Mayfield bypass which remained free, the parkway was originally a toll road, as were all Kentucky parkways. State law requires that toll collection ceases when enough tolls are collected to pay off the parkway's construction bonds; that occurred in 1992. It is constructed similarly to the Interstate Highway system.

The Julian M. Carroll Purchase Parkway from the junction with Interstate 24 west has been legally designated to become part of Interstate 69. On May 15, 2006, Governor Ernie Fletcher announced that the Purchase Parkway would become part of the alignment of Interstate 69 in Kentucky, along with parts of Interstate 24, the Edward T. Breathitt Parkway, and the Western Kentucky Parkway[citation needed]. To reflect this, Future Interstate 69 shields were erected along the parkway in the summer of 2006. Additional federal legislation enacted in 2008 (see above) confirmed the route of I-69, and authorized Kentucky to immediately begin signing the Purchase Parkway (and parts of the western Kentucky Parkway and Edward T. Breathitt Parkway) as I-69, even though the parkways do not yet meet interstate standards.

The Parkways, however, do not meet current interstate highway standards and will eventually need upgrading. The reason the 2008 legislation (HR-1195) immediately applied the I-69 designation to the Purchase Parkway is to tap into federal interstate highway money to fund upgrades to the parkway. This is because interstate highway funds typically could not be used to upgrade an existing freeway until it is designated and signed as an interstate. A larger 36' median, increased bridge heights to 16', shoulder improvements, and interchange reconstructions will all need to take place to bring the alignment into federal compliance. No official funding has been set in the six-year plan stipulating modernization of the parkways that will be affected by Interstate 69's routing, nor has any official study been completed.

Because Kentucky is using an existing expressway for I-69, highway officials will likely avoid years of costly environmental studies required by other states, as the upgrades are being performed within the footprint of the existing highway.

Funding remains the big issue for upgrading the parkways to I-69, as there is no funding in the state's 2006 Six-Year Transportation Plan specifically for I-69. However, it is likely that Kentucky will perform the required upgrades on individual segments of the Purchase Parkway when the pavement reaches the end of its lifespan, through "Pavement Preservation Projects." This approach is similar to the way New York is upgrading its substandard Route 17 Expressway to I-86.