Most model railroaders have far more cars (rolling stock) and locomotives than they can possibly operate at once. One option is to simply store excess rolling stock and locomotives in boxes or on display shelves or cabinets. It is possible, however, to store all of your extra equipment and trains on tracks in a yard that may or may not be part of the visible operating portion of your model train layout.
However, design mistakes are a common feature of model railroad yard layouts. Yards don't always work out as well as they should. A major cause is the lack of available information on how to design a good model railroad yard layout. Without the resources, model railroaders are forced into a lot of guesswork.
Model Train Yard Layout Compression
Apart from the lack of available information on model railroad yards, another cause for less than satisfactory model railroad yard designs, is the need to compress a model railroad layout into the space available. 'Compression' is the model railroaders enemy, but in most cases, necessary.
Let's start by looking at the make up of real classification yards. Generally, they are huge. They often consist of many smaller special-purpose rail yards, that collectively, add up to a complex array of train track.
It is commonplace for there to be three separate double-ended rail yards strung one after the other. These are designed to move train traffic efficiently and usually comprise: an arrival yard, a classification yard, and a departure yard.
The Arrival Yard On Model Train Layouts
The arrival yard is where arriving trains drop off the cars of their train. The cars are then moved to the classification yard, being switched back and forth as necessary to get the right cars onto the right trains. The trains are then built out and moved to the departure yard. After getting a new caboose and locomotive, they then proceed to their next destination.
For more information on yard designs read the best-selling Model Train Help ebook by Robert Anderson (Highly Recommended).