The source outlet of the somewhat longer left upper reaches from the Eckenbachgraben shifts with the karst water level of the Swabian Alb.
The Steinlach enters the Steinlachtal near Talheim in the Alb foothills and is then strengthened by the Weiherbach, which is longer at its mouth and has a much larger catchment area.
On now straightened run through the Tübinger district Derendingen and finally through the southern part of the city centre of Tübingen, it reaches the Neckar, to which it flows from the right at about 317.5 meters above Sea Level, less than half a kilometre below the Neckarinsel.
The following neighbouring rivers behind, of which only the Katzenbach and possibly also the Bühlertalbach have some importance, drain the forest area of the Rammert, which extends adjacent to this side to the estuary of Tübingen.
At morphologically hard rock layers waterfalls occur, for example at the Untere Mühle near Mössingen and northeast of Ofterdingen not far from the sawmill.
At its mouth it has deposited an overhanging gravel fan, which pushed the course of the Neckar to the north and on which parts of today's southern city of Tübingen were built.
A section of the creek bed between Schillerstraße and Uhlandstraße was put under protection as a geological natural monument Ofterdinger Schneckenpflaster, because there are especially many stone cores of the name-giving ammonite Arietites bucklandi on the surface.
The entrance of the stone puddle into the layers of the Lias Alpha near Ofterdingen caused the deflection of the course to the northeast and let the waterfall below the village develop.
Due to the humid climate with abundant precipitation throughout the year and the almost constant water supply, numerous Old Germanic villages were founded along the Steinlach (Mössingen, Ofterdingen, Dußlingen).
At the same time, the mechanical-biological collective sewage treatment plant of the Abwasserzweckverband der Steinlach-Anliegergemeinden south of Derendingen as well as numerous rainwater retention basins were built.