Battlezone was an old arcade game released by Atari Games way back in 1980.
The game
This is a basic wireframe 3D tank hunting game. You control the action from a first person viewpoint. Your enemies are tanks, flying saucers, and missiles. The only point of the game is to stay alive. You have a radar scope at the top of your screen that gives you a basic view of the area (although you are really only attacked by one tank at a time). Scattered around the playing area are various geometric shapes, which serve as both obstacles and protection.
The background of the game is a simple mountain range that includes an active volcano. The volcano was the source of many rumors back in the early 80s, but the programmers have continually insisted that it is just a window dressing, that there is no secret castle, alternate world, or anything else inside (not that you can reach it anyway). The volcano was coded into the game by Owen Rubin (the same guy who designed Major Havoc). He was not even on the Battlezone team, he just really thought the volcano should erupt, so he wrote the code for it himself.
The strategy behind this game is simple. Do not let enemy tanks get their turrets pointed at you. Avoid this by moving and turning at the same time until you can get a straight shot at them. While missiles are best handled by backing up continually while firing at it until you hit. Flying saucers also appear from time to time, but they are only a diversion, you do not have to shoot them at all.
There was an alternate version of Battlezone developed that is called the "Bradley Trainer". This version was made for the US Army, for use as a tank trainer. The stories on this version vary wildly. Atari claims it was never built, some retired Atari employees claim there were only two of them, and at least seven different people claim to own one, or know where one of them is stored. The only thing that can be said for certain about the "Bradley Trainer" was that there was at least one of them, because the Videotopia arcade exhibit has one.
Where to play
To properly play Battlezone you are going to have to locate a real machine. For close approximations you can play the MAME version on your personal computer, or try one of the console ports that were released in the early 1980s.
This is a great game for your arcade game collection, but it is very expensive. This title can also be problematic, but luckily it was very popular, and most common problems have already had easy fixes developed for them.
I myself acquired a Battlezone machine in the Summer of 2003 for free. It was missing the monitor and the boardset but was otherwise complete and in awesome condition. Eventually I will get around to getting it working.