One of the few places on the planet where tank battles are taking place is, Afghanistan. Not only that, but the tanks used are half century old T-55s. Actually, the T-55s seeing combat are not that old (they were built 25-30 years ago), although the design is. Many warlords in Afghanistan still have a few T-55s in running condition. American troops have seen, or heard, the T-55s fighting in out. Tank to tank. Especially in Western Afghanistan, where several tribes are fighting it out for control of Herat.

The T-55 is a 36 ton tank with a four man crew and a 100mm main gun. There is also a 7.62mm machine-gun mounted next to the big gun, and a 12.7mm machine-gun mounted on top of the turret. The tank carries 43 100mm shells. The basic T-55 hasnt got a lot of armor (99mm on the chassis front, 203mm on the front of the turret.) However, the standard 100mm anti-tank rounds for the T-55, only goes through 180-200mm of armor. So when two T-55s are shooting at each other, you either have to put the shell in the right place, or have one of the more expensive HEAT shells, which can penetrate 380mm. But HEAT rounds dont age gracefully, and the Afghans have a lot of very ancient ammunition. This means that even the armor piercing rounds will often not fire, or if they do, not do so with full power. 

The T-55 was designed in the late 1940s (as the T-54). The T-55 entered service in 1958, nine years after the T-54. The T-55 incorporated many small improvements, a new turret and better engine. Russia kept producing the T-55 until 1981, mainly for export. Poor Third World countries liked the T-55, as it was easy to use and maintain, and was useful for civil wars and keeping the population under control. For this reason, they remain in use in many poor countries, including Afghanistan. But because several warlord factions own many of the T-55s in Afghanistan, these tanks fight each other from time to time. 

The Russians sent the Northern Alliance at least 40 T-55s in 2001, to help in fighting the Taliban. A few more modern T-62s were sent as well. In turn, the Taliban had bought 150 T-55 tanks in 2002. Exactly who they bought them from is unclear, although the tanks appear to have come from Ukraine. The Russians left in 1987, and gave the pro-Russian Afghan government several hundred T-55 and T-62 tanks, and other armored vehicles. While many of these T-55s have been destroyed in the last two decades, enough are left to provide the only tank battles you will encounter these days.