Look down the barrel of this 120 mm mortar used by US Marine artillery units

Daniel Brown/Business Insider

A Marine next to the 120 mm mortar system.

The US Marines hosted Marine Day this weekend in New York City, where they held demonstrations and showed off some of their vehicles and weapons.

One weapon on display was a 120 mm mortar system - the biggest mortar system the Marines have.

It's moved to, from, and around the battlefield by an Internally Transportable Vehicle (ITV), which is basically a jeep that can be used for transporting multiple weapons systems and even reconnaissance.

The 120 mm mortar system is actually a French design that entered service in that country in the 1990s. The US Marines began using it in Afghanistan in 2001.