How wide should a layout be?

In theory, the only limit to the width of your layout is the amount of space you have available. The reality is slightly shorter: bear in mind that if you have a derailment you will need to be able to reach your locomotives, coaches and wagons.

If you have your layout against a wall, you do not want to be stretching over your layout which may lead to damaging your scenery.

For these reasons, the maximum width you can realistically reach safely is about a meter (a bit more than 3 feet). This means the maximum width of a layout should be about one meter.

Ideally, you need access to all parts of the layout. This is why many railway modellers choose to build their layout around a central well allowing them to sit in the centre of your layout.