The 3rd United States Infantry Regiment is a regiment of the United States Army. It currently has three active battalions, and is readily identified by its nickname, The Old Guard, as well as Escort to the President. The regimental motto is Noli Me Tangere (from Latin: – "Touch Me Not"). The regiment is a major unit of the Military District of Washington (MDW).

The regiment is the oldest active duty regiment in the US Army, having been first organized as the First American Regiment in 1784. It has been the official ceremonial unit of the US Army since 1948.

The Old Guard's current duties include, but are not limited to, providing funeral details at Arlington National Cemetery, guarding the Tomb of the Unknown Soldier, providing honor guards for visiting dignitaries, supporting official ceremonies and providing a quick reaction force for the Washington, D.C. area.

As of 2018, there were three active battalions of the 3rd Infantry Regiment.

https://en.wikipedia.org/wiki/3rd_U.S.Infantry_Regiment(The_Old_Guard)

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