Brașov is the obvious day trip — one of Transylvania's finest medieval cities, only 12 km down the mountain. The Black Church, the old town square, and the surrounding fortress walls can fill a comfortable half-day. Bran Castle (the "Dracula's Castle" of tourist marketing, though the Vlad the Impaler connection is thin) is 30 km away, and the spectacularly ruined Râșnov Fortress is closer still. All three are easily combined in a single day by car.