It usually takes about 15 minutes.
The car drop-off takes even less. Arrive on time, in a clean car, with the agreed amount of fuel in the tank. You hand over the keys, and the rental agent inspects the car and signs your copy of the drop-off report. If the deposit is not refunded immediately in cash, please keep all documents until you receive your money back.
Be sure to explore scenic old Zagreb. It is one of the few places on earth where you can walk through the ancient streets at dusk and see the lamplighter manually lighting the street lamps.
The car will take you up to Sljeme, the highest peak of the Medvednica range. You'll enjoy gorgeous scenery, explore Medvedgrad Castle, and finally, have dinner in one of the mountain chalets surrounding the castle, which serves homemade Croatian food.
An hour's drive from the capital is the Plešivica wine region where you can taste the famous red wines. Plan an overnight stay because there's no way you can resist wine tasting!
Be sure to go to Plitvice Lakes, take selfies against the waterfalls, and order a trout dinner at the restaurant.
Krka National Park is one of the most interesting places along the coast, with crystal clear sea, steep mountain slopes, famous Skradinski Buk waterfall, medieval fortress, and... a Michelin-starred restaurant.
Don't miss the amazing town of Kaštela, which is an agglomeration of seven villages. Each has its own ancient fortified castle!
And of course, the Croatia experience wouldn't be complete without some leisure time at a top beach in Brela (according to Forbes).