How far is it from Split to Zagreb?
Split is 4 hours drive by car from Zagreb on motorway, 410 km.
Zadar is even closer, 3 hours drive, 280 km.
If you prefer to take local roads you need to get out of the motorway at Karlovac, carry on along through a picturesque region of Lika. On a way you can visit Plitvice Lakes Plitvice Lakes
or village Smiljane, a birthplace of great scientist Nikola Tesla. Nikola Tesla Birthplace
If you are not in hurry, I would certainly recommend this.