Drove to Frankfurt, very hot day. Decided to pass on the 3 hr frankfurt by foot tour and do our own. Started at Romerberg historic market square with it's 1/2 timbered houses, fountain and the Rathaus (city hall). Walked to Kaiserdom St. Bartholomaus 1239. Onto Zeil street a shopping promenade. Drove 30 minutes to Mainz on the Rhine. Walked to the Wood tower, one of the three remaining towers from the city wall. Onto the markt where one can see the cathedral dom above the shops. Had dinner at a 400 year old bar, Brauhaus zur sonne. Arrived at 7 pm joining just a few patrons for great food and service. By 8 the place was full. Took a stroll along the Rhine river to our hotel. Drove across the river to the castle museum.