Meet at Eiserner Steg (Mainkai) in central Frankfurt a little before the time you picked for your departure. Make sure to get the seat that will suit you best on the voyage—you can pick to sit up top outdoors or indoors where it's warmer by a window.
Depending on what route you choose, your trip could be going upstream to Gerbermühle (Offenbach) or downstream to Frankfurt-Griesheim. If you chose to go upstream, some of the spots to see are the Frankfurt Cathedral, Dreikönigskirche, Sachsenhausen, Literaturhaus, Main Plaza, European Central Bank, and Gerbermühle. If you chose to go downstream, keep an eye out for Frankfurter Römer, Paulskirche, Commerzbank, Städel Museum, Westhafen Tower, and Griesheim.
Much of Frankfurt was rebuilt after WWII, and you can take in many of the city’s well-known sights as your cruise along the Main River. When your ride is over, return to your original departure point to get on with your day.