I think that this is perfect hotel for those looking for an authentic feel of Split with contemporary simplicity and comfort. I really loved this place, and although it is a much pricier option (about 200 euros per night) than staying at a guesthouse, the atmosphere and location are perfect. A unique mix of ancient and modern, tastefully assembled. Hotel Vestibul is located in the Vestibul area of Diocletian's palace, an ancient Roman empire palace that is the big landmark in Split. You'll be footsteps away from the city walls and main palace cathedral, which was built after the fall of the Romans. You can check out their website which has pictures of the rooms here:
www.vestibulpalace.com/eng/opis_hotela_vestibulpalace.htm