Furtwangen from Freiburg without a car

"Is it possible to get to Furtwagen and/or the Black Forest Open-air Museum without a car from Freiburg?" "Rabbi, tell us, is there a blessing for the Czar" (Fiddler on the Roof). Rabbi "There is a blessing for everything." Although you could go by bus from Freiburg to Furtwangen, or by rail from Freiburg to Triberg, then down the Gutach (Schwarzwaldbahn) to the Schwarzwald Freilicht Museum, I think the fastest way is down the Rhein to Offenburg, then by regional trains to Hausach. From Hausach, there are about 10 bus per day, roughly every hour, to the Museum.