Hello, I have an upcoming long layover of 15 hours in Vienna. Arrive around 8 AM and leave around 9 PM. Obviously going to go into the city. What would be the ideal itinerary to see the major sites of the city? I also want to inquire for a day room at a Hotel. What location is best that is near CAT station to airport and walking distance to the major sites and near bars/restaurants?

Thanks for all the help