Retaining walls
Gray blocks with caps
Blocks with caps
Warmed toned blocks
This is the kind I used for my mom's place, that I bought at Mutual Materials near Tualatin. I got the earth toned instead of gray, since I feel the warmer tones help liven up our gray days in the winter and go so well with vegetation. Just a matter of preference on the tone (warm or cool)
Sometimes walls can be built of the remainder of the concrete slabs left over when someone breaks up an old driveway. It has a nice look, is recycled, and the blocks stack in a pretty way also providing good balance and run-off behind for the drainage (but it's still important to install gravel and a drain behind the wall
Stacked rock wall - traditional, time consuming, must match rocks with each other like puzzle pieces
Q