A retaining wall allows you to turn a useless (for landscaping purposes) slope into a terraced, flat area. And perhaps the easiest way to build such a wall is with used railroad crossties.

I’ve watched many retaining wall videos that are filled with very bad information. I urge you to seek the advice of a structural engineer for any wall taller than 6 feet.

However, modern segmental retaining walls (SRWs) emerged in the late 20th century when engineers developed high-strength concrete blocks with interlocking features. The introduction of geosynthetic ...