Concierge.com's insider take:

Though there's been some kind of a fortification on this site for more than 3,000 years, the existing castle is largely 16th- and 17th-century. There's not much to it these days, other than the grand old rooms—which host concerts, temporary exhibitions, and other events—and the Virtual Museum, which tries to re-create Ljubljana's past with the help of computers and 3-D displays. But the vantage point from the stone castle is exceptional, and a drink at the outdoor castle café is the perfect way to recover after trekking up the tower's 150-step spiral staircase. Directly below you is a panoramic view that stretches from the snowcapped peaks of the distant Julian Alps down to the terra-cotta-tiled roofs and the lazy green Ljubljanica River. The castle is reached via a steep hike through woodland that's carpeted in springtime with wild orchids and violets, though late 2006 saw the opening of a modern funicular that zips you up the hillside in just over a minute.