I'd assume that someone in the community of Moegglingen is protesting against a road/highway being pushed through the town. "B 29" sounds like the name of a German road route, not an autobahn, more of a "local artery".
Words above read "Freedom for Moegglingen", hence the Statue of Liberty.
Edit - According to Google Earth, the B29 passes directly through Moegglingen, using the old main street as part of the highway, no bypass.