We will be visiting Nuremberg and Munich for a few days after a rive cruise and wanted to know what is the best way to see the area? Is the train a good option and should we take a tour?
You can definitely take the train, Germany has a great public transportation system.
Visit deutschebahn.com for information about pricing and the connections.
I would also consider renting a car. The fastest way getting from Munich to Nuremberg is by car, but you won't really need one in the city.
I could recommend you to go there by train. It takes 1 till 1.5h. In Munichyou will find a perfect public transportation system.
We started our Germany trip in Munich and drove from there to Nuremberg. It is an easy drive, if you want to freedom of having a car. However, train travel is always a good idea too. I wouldn't say you need a tour, but you can certainly utilize a tour guide at various sites (for example-take the guided tour of Nymphenburg Palace). Both cities are very easy to navigate, and the city centers are small and compact.
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Also, the InterCity (IC) and InterCity Express (ICE) trains are an easy way to get from Munich to Nuremberg - maybe a little costly, but my experiences going all around Germany on ICE trains was great. They were always on time, spacious and comfortable. Just make sure to pick the Hbf (hauptbahnhof) station options - they are the 'main stations' central to the city centres.