Are there any good historic sites to visit in Boulder?

I like the creek path along Boulder Creek, there is the statue of Chief Niwot, an Arapahoe that left the valley after trying to make peace with the white folk only to lose his land. The "Curse of Niwot", it is said that when he was finally pushed out of the valley he said that anyone who settles there will feel an unexplained urge to take care of the valley and will not be able to easily leave...some say Niwot's curse is why there is so much environmental passion for the valley;) Kinda interesting and sadly Chief Niwot was later killed in the Sand Creek Massacre in the SE of Colorado just a few years later after being driven out of Boulder