The 11 most incredible weapon systems used by the Russian army

Russia had the world's fourth-largest defence budget in 2015, at a cost of $66.4 billion (£46 billion).

For that, the state boasts 845,000 troops, 22,550 tanks, and 1,399 combat aircraft.

The country might not be considered the superpower it once was, Russia's armed forces have gone through a significant transformation since President Vladimir Putin's reelection in 2012.

The army is being split into smaller, more dynamic brigades. The focus is on new technologies rather than brute manpower. (For instance, this Pantsir-S1 anti-aircraft system is basically a tank with a load of extra cannons sticking out of it.)

Here's a review of some of Russia's more menacing military machines.

Tomas Hirst contributed to this slideshow: