Aalborg is Denmark's fourth-largest city, anchored on the Limfjord in North Jutland, and it is worth clearing up a common point of confusion first: Aalborg does not have its own airport code for car rental purposes, since ZTG refers to the city's rail designation rather than an airport. The good news for anyone searching car rental in Aalborg is that the city's actual airport, Aalborg Airport (AAL), sits just a short drive northwest of downtown, minutes rather than hours away, and it is a genuine, fully functioning airport with on-site rental desks run by international and local companies.
For most visitors, the simplest approach is to fly into or arrange pickup at Aalborg Airport directly and drive the short distance into the city center, rather than searching for rental options tied specifically to the city's train station. Once you have a car, Aalborg itself is easy to explore and use as a base: the E45 motorway runs south toward Randers and Aarhus, while local roads head north toward the beaches and dune landscapes near Blokhus and Rubjerg Knude, both popular day trips of well under two hours from the city.
Driving in Denmark is on the right, and the roads in and around Aalborg are well maintained and toll-free on the motorway network, though the Great Belt and Oresund crossings further south carry bridge tolls if your route extends that far. Winter in North Jutland brings occasional snow and strong coastal winds, so some seasonal caution is worth building into any itinerary between late autumn and early spring, but overall Aalborg is a straightforward, well-connected base for exploring this part of Denmark by rental car once you've picked one up at the nearby airport. Returning the car to the airport rather than a downtown branch is usually the simplest option for anyone flying onward.