Sammie points out the efficiency (in terms of space) of using equilateral turnouts. If I may be permitted another European example, there is the "famous" -- at least in Europe -- "Semmering pattern" used in the layout of several smaller stations on the Semmering line, where essentially all the turnouts are equilateral, and have been so since the beginning.

The Semmering line from Austria -- south of Vienna and ultimately heading toward Italy -- was built between 1848 and 1854 and is considered Europe's first standard-gauge adhesion mountain railroad. It was built double-track from the beginning and still operates on essentially the same alignment, though there have long been plans to build a base tunnel to bypass the steepest and most curvy section of the line.

The line was designe by Carl Ritter von Ghega, one of the pioneers of European railway [civil] engineering. It was he who came up with the so-called Semmering pattern.

For more information on the Semmering line and photos, see the Wikepedia entry at Wikipedia Semmering article.

One of my photos on the Semmering line is here: Semmering viaduct photo. I have done cab rides on this line.

The Semmering railway has been designated a UNESCO world heritage site.


I think I can describe this track pattern reasonably well, without being able to draw a diagram. Just before the small stations, the two main line tracks are spread slightly further apart than normal. Then, each of the main line tracks has an equilateral turnout which in the center, connects into another equilateral turnout.

In other words, the line goes from two tracks to three tracks in the station area. The same pattern of three equilateral turnouts is repeated at the other end of the station to change the line back to double-track.

The center track can be used for trains to meet or pass each other -- or to traverse from one main to the other.

The station building is located one one side or the other, on one of the outer tracks. There is also an island platform between the two other tracks, so all three tracks can be used by passenger trains. (Some of these small town stations still have some service by local (commuter) trains, while others are now used only for meets and passing of both passenger and freight trains.

The normal Semmering pattern applies where the station tracks are on relatively flat terrain. Where the station tracks themselves are located on an incline, the lower end has runaway tracks for the outer two tracks -- sometimes with two more equilateral turnouts. In other words, you have FIVE equilateral turnouts at the lower end. These runaway tracks aren't really used as such but are now used mostly to store MOW equipment.


I hope this description makes sense. When I had grandiose plans to build a model railroad based on Austrian prototype, I planned to include at least one station in the Semmering pattern. Of course, that was before I realized what a huge investment of both time and money such a model railroad would represent.

-- Ernest