Hello, I will be travelling to southeast Europe this July from Detroit, USA (Lufthansa airlines) and I have a layover of 11 hours and 20 mins at the Frankfurt airport. I think this would be more than sufficient time to see some of the city. From the little research I've done, I've found out that the airport is in the city only about 7.5 miles from central Frankfurt.
I've never left an airport on a layover before so how do I go about doing this? And what should I see and do in the hours I have? And what is the best method of transportation to get from the airport to the city-centre?
Also, the layover is from 9:10 am to 8:30 pm and the flight is to Ljubljana with Adria Airways. I will be travelling with one other person. Any advice is greatly appreciated, thanks!