Ludwigsfelde is a small industrial city with around 23,000 inhabitants a few km south of Berlin.
From Berlin use the RE3 or RE4 to the Ludwigsfelde station (22 min). From Potsdam and Schönefeld Airport use the RB22 to the station Ludwigsfelde Struveshof. As the station is a bit outside of the city, the vbb (dead link: February 2023) gives information on how to reach the city (german, pdf, plan of the bus network of the city included).
Ludwigsfelde is directly connected to the Autobahn A10 ("Berliner Ring").
There are multiple bus connections to Potsdam and one bus every hour to the Berlin S-Bahn station Buckower Chaussee, but you will most likely prefer to take the train.
The town centre is not that big and should be even walkable (also there exists a bus network), the whole city including all districts (11 small villages) has a size of 110km² - if you want to visit those, a car would be advantageous.
The bus network is centered on the train station of Ludwigsfelde, for a network map see the pdf above, timetables can be found here (dead link: December 2020).
Kristalltherme Ludwigsfelde, 52.305278°, 13.262222°, +49 3378 518 79-0. be prepared, people are usually nude there.
Riding - there are several horse-riding centres around Ludwigsfelde and many ways, links to them are here (dead link: December 2020) (German)
Hiking
Berlin and Potsdam to the north, or the beautiful and unique Spreewald Region to the south.
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