How tall can a mortarless stone retaining wall be?

The maximum height of a mortarless stone retaining wall is dependent on the type of interlocking stone blocks that you decide to use. There are different manufacturers of stone blocks, and they have their own specifications and limitations, when it comes to things such as height and lateral pressure they can take. The height of your wall also depends on the type of soil that you are placing your concrete blocks onto. If the soil is somewhat soft and unstable, the maximum height of your stone retaining wall goes down, due to stability and safety factors.