Bahnstromleitung Neckarwestheim–Zazenhausen, High-voltage traction power line near Stuttgart, Germany.

The Bahnstromleitung Neckarwestheim–Zazenhausen is a 26-kilometre railway power line built in 1977, running from the traction current switching station in Neckarwestheim to the Stuttgart substation in Zazenhausen. It is the only line in the German railway power network built with four-bundle conductors, giving it higher transmission capacity. For much of its route it shares masts with 220 kV and 380 kV three-phase lines, using lattice masts with up to five crossbeams.

Built in the mid-1970s by Energie-Versorgung Schwaben, the line entered service in 1977 to carry 16.7 Hz traction current from Neckarwestheim nuclear power plant's single-phase generator to Stuttgart. Until that plant started up, railway power for the Stuttgart area had come from the Münster power plant since 1933, which also fed the 110-kV line to Munich. The new line was built alongside a two-circuit 220-kV AC line on shared masts.

The line's name comes from its two endpoints: the railway power switching station at Neckarwestheim and Stuttgart's Zazenhausen substation, built for this connection. Along the route, look for the 2012 crossing mast near Marbach, which resembles a branch mast with an extra lower crossbeam added for the railway circuit. Near Pattonville, low masts with only two crossbeams stand because of the former military airfield.

The line crosses the Neckar three times: south-west of Pleidelsheim, near the Marbach power station and east of Neckarweihingen. Near Pattonville, low masts with only two crossbeams stand because of the former military airfield. A crossing mast built in 2012 near Marbach is worth a look.

This line uses a special four-bundle conductor configuration in its power cables, a feature that sets it apart from other German railway power lines. This technical approach allowed engineers to significantly increase the power capacity without fundamentally altering the mast structure.