Interstate 75 in Kentucky

I-75 (and I-71) heading northbound into Cincinnati from Covington

I-75 runs roughly parallel to US 25 for its entire length in Kentucky. The freeway enters Kentucky south of Williamsburg in the Cumberland Plateau, bypassing Corbin and London before descending into the Bluegrass region near Berea through the Pottsville Escarpment. The highway continues north through Richmond en route to Lexington. It meets and then becomes briefly concurrent with I-64 along the north and east sides of Lexington, before leaving the Lexington area northerly and bypassing Georgetown en route to Cincinnati, Ohio. Just south of Florence, the route enters the Cincinnati metropolitan area and becomes concurrent with I-71. The two routes remain concurrent through to Downtown Cincinnati. On the north side of Florence, I-75 intersects with the only auxiliary route it has in the state, I-275, a beltway bypass of the greater Cincinnati area. It then passes through Covington and crosses the Ohio River via the lower level of the Brent Spence Bridge into Ohio.[3]

The stretch through Covington originally included hills and curves steeper than those recommended for Interstate Highway standards. As a result, the northbound descent into Cincinnati, known as Cut-in-the-Hill, was nicknamed "Death Hill".[4][5] It is a steep descent into the valley of the Ohio River between Kyles Lane and the Brent Spence Bridge leading into Downtown Cincinnati.[6] The hill is known for its high number of automobile accidents.[7][8] In 2006, the Cut-in-the-Hill averaged over seven times more accidents when compared to similar roadways in Kentucky.[7]

At the Cut-in-the-Hill, the northbound road takes a sharp left turn into a steep grade down to the Ohio River—about 370 feet (110 m) in four miles (6.4 km).[9] Accidents are usually attributed to a combination of speeding, curvy lanes, poor weather, longer stopping times for trucks traveling downhill, and traffic congestion.[7]

The area earned the sobriquet "Death Hill"[9][10] shortly after I-75 opened in 1962.[9] By 1968, a total of 23 people died in crashes on the hill,[9] so a concrete wall was installed to separate northbound and southbound traffic.[9] The wall helped reduce fatal crashes, but accidents continued, and, in 1977, the hill averaged 583 automobile accidents per year.[9]

In 1986, a tractor-trailer lost control, leading to an accident that caused a Northern Kentucky University student to burn to death in his car.[9] As a result, Governor Martha Layne Collins banned most northbound tractor-trailer traffic from the hill.[9] From 1989 until 1994, $50 million (equivalent to $84.1 million in 2021[11]) in reconstruction was spent to straighten the hill's S-curve and add a fourth lane for southbound traffic,[7] and, in 1995, the truck ban was lifted.[7] Also as part of the reconstruction, ramps were added at Pike Street to give complete access, while an interchange with Jefferson and Euclid avenues was obliterated.[4]

In 2006, the hill and the Brent Spence Bridge saw 151 crashes in the northbound direction and 121 crashes in the southbound direction, totaling 272 in all.[12] To help reduce the number of accidents, a flashing "Steep Grade" sign was installed[12] and a Kentucky State Police trooper was assigned to patrol just the Cut-in-the-Hill.[7] Additionally, eight radar speed signs were installed in 2007 to remind motorists to drive a safer speed.[13]

The Cut-in-the-Hill was originally designed to carry up to 80,000 vehicles per day, but, in 2006, it carried 155,000 daily.[7] Kentucky officials are reportedly working to raise more than $2 billion to replace the section of highway,[7] but, as of 2012, no construction is planned.[7]

• Media related to Interstate 75 in Kentucky at Wikimedia Commons