“Gothic spires, medieval gateways, Soviet blocks and a huge Hollywood-style sign: Braşov’s skyline is instantly compelling. A number of medieval watchtowers still glower over the town. Between them sparkle baroque buildings and churches, while easygoing cafes line main square Piaţa Sfatului.” – Lonely Planet
Whether coming from Bucharest of elsewhere in Romania your best option is going to be the train. You can check prices and schedules HERE and in busy season (Christmas, Easter and summer) it is advised to book in advance. You can also buy directly from the train station. Travel time ranges between 3-4 hours depending on the train and less than 50 lei (€10).
Since the most popular activities are located outside the city you could also rent a car to give yourself more flexibility. A third option, especially if you are short on time, is to do a guided tour from Brasov or Bucharest. Transportation and guides are provided which takes the pressure off but it is also very structured and rushed.
Castles: If you only do one, do Peles. Bran has a cool look and feel and I enjoyed it, however, Peles is just stunning.
1.5 – 2 days. I was short on time and did a day trip from Bucharest. It was nice getting to see Bran and Peles plus a walking tour of the city but I would’ve liked to see the city a little less rushed for time. If you have the time, two days and one night (including travel time) would be perfect.