Retaining wall block – If you want authentic resistance, you should do concrete. To do this, you’d have to dig more than their own garage band, for mounting a form work on both sides of the wall. Place the rebar and concrete fill, if possible truck (central). The wall usually has a minimum thickness of 10% of the height. If you resort to a specialized company could build a wall of reinforced concrete (which is how the pools are built); put armor on the ground straight cut and cast concrete with hose. It is a perfect solution that requires after a smooth finish leave.
Retaining wall block, another simpler but equally effective system is to use concrete blocks to assemble. They are concrete blocks as traditional (gray, 40x20x20 cm) but with larger holes to match them vertically and fill concrete and a pair of corrugated steel bars; and also have a pair of grooves to place a horizontal reinforcement (sometimes also called blocks in H by the way they like the letter).
You could get to make the brick wall, but then you should build buttresses that introduced into the ground (the part that remained buried), which were very well linked to the main retaining wall block (better with straps or stainless steel keys) and practically have one every meter. In all cases you must make a shoe run under the wall to the foundation. It is a shoe important dimensions, as you can easily reach 1.5 m wide, and is “connected” to the wall with metal also rods.