How long would a horse and cart take to travel 106 km on hilly country?

In August 1888 Bertha Benz and her two sons traveled from Mannheim to Pforzheim in Germany (a distance of 106 km) using the Benz Patent-Motorwagen No. 3. She took 12 hours and 57 minutes to traverse the distance (with several short stops due to technical problems). How long would it take a horse and cart to travel that distance (on hilly country, with limited stops)?