Darmstadt stickpin

[Ingsoc]

I bought this stickpin of the German city Darmstadt at the local market for one dollar, could someone give me more deatails about her, like what was it's awarded for and the year of making?

[G.F.C.]

It was made probably from 1960 onward, and awraded to the first tourist that paid 75 pf for it.