The website "Weimar im Nationalsozialismus" (German Version) can be found here.
The access road to the camp, constructed by inmates. From mid 1938 to late autumn 1939, brutally and mercilessly goaded on by the SS, inmates were compelled to construct a five-kilometre-long connecting road from the Weimar-Ramsla state route to the concentration camp on what had formerly been a dirt road through the forest. The inmates called it "Blood Road ". A section of the original concrete road has been preserved.