Recommend a day trip to Koenigswinter and Drachenburg
Beethoven house is worthy to...
Beethoven house is worthy to visit. If you like music or museum, i will suggest you to stay around 2 hours.
The restaurant next to the old city hall is also great. It's older than 600 years with good price.
Grocery shopping, such as dm or Rosemann or A+ is everywhere.
Christmas market is really good