We have visited the archeological museum just as a killing time while waiting for our Batorama trip, it turned out to be better as expected, a lot of items exhibited and thoroughly covered from the history´s point of view. Even incited us to visit other towns in Alsace. Btw, with a Batorama ticket you get a 20% discount from the 6 euro ticket. But if you plan to visit more than one museum, I would recommend the Strasbourg Pass, 14.5 euros for 3 days that includes several museums, among which the ones in Palace Rohan, the trip on Batorama, and a couple of other 50% discounts. There is also a one day Pass, but I have no idea how much that costs.
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