Easy Border Wall?

I have a border that I need to build a small retaining wall. The border is about 40' long and I need a wall about a foot high. Years ago I would have had the sand, cement & blocks delivered and set about it. But now due to age & health this project would be too difficult for me to tackle in this way. My question, Is there a simpler way with new materials that I could handle? I would prefer something that maybe had the appearance of a stone wall or similar. I have used log roll elswhere, but would like something different. Any help would be appreciated.

Ivor Mills

What about sleepers?

They come in decent lengths and are sturdy, will last a lifetime

check out your local landscaper , they will give you a ton of ideas.