Before you start building a stone retaining wall, it's important to assess your garden's landscape and determine where the wall will be most effective. Take note of any slopes, erosion-prone areas ...

Draw a 21-in. radius circle with the string and marking paint. Lay the first row of retaining wall stones (12 in our case) ...

The goal? To build a 20 foot (6 meter) and 213 ft (65 m) long dry-stone wall as part of a park where the landscape was digitally planned, and the earth autonomously excavated. The coolest thing ...