I would recommend to visit the museum when the outdoor-area is open and there are activities running. We went there on a chilly Sunday in June, and in that type of weather, it was quite the perfect place to visit. Two trains operate on the outdoor-premises, there is a carrier with a small cafe - reasonably priced.
The indoor-facilities (exhibitions) are also very nice, although an upgrade of some of it would be fitting. The children can build their own tracks, very popular. All in all, a clear recommendation, most notably in the summer season.
Good to know: In the winter season, there is free admission on Saturdays. Visit the website for updated info.
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