Let KAYAK do the searching
Based on KAYAK hotel searches, the most popular destination is Frankfurt am Main (65% of total searches to Franken). The next most popular destinations are Heidelberg (18%) and Nuremberg (12%). Searches for hotels in Rothenburg ob der Tauber (5%) are also popular.
KAYAK users have found double rooms in Franken for as cheap as $48 (Heidelberg) in the last 3 days. The average price is $225.