We visited on a Thursday afternoon and by luck, arrived just after a big group of teens left the museum. There were few visitors besides us which made it an unhurried time, ideal for my 4 year old. We spent about 2-3 hours wandering leisurely throughout, including a relaxing late lunchin the cafe. All their exhibits were good, although I wish there were more hands on displays (I.e. Brussels' dinosaur exhibit). The huge central display of large skeletons was excellent. We all enjoyed the taxiderm rooms... Completely fascinating! It was neat to also see the exhibit from Grube Messel, which is in nearby Darmstadt. For non-German speakers, most every species is labeled also in English, but the descriptions are in German which may bother you if you're one who enjoys reading every single plaque. For those with kids, there's a small but well stocked play area (toys, small table with coloring pencils, children's books) on the 2nd floor of the restaurant. Seating is very plush there, with a modern lounge vibe. Try the menu specials as well as ordering off their menu (found on the museum website). If you would rather not eat at the museum, there are some nice cafes nearby as well as Boeckenheim weekly Market right around the corner on Thursdays. (We stopped through there enroute to the nearest parking garage).
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