The Wardens of Lorien were elven patrols that operated in small groups. They defended the borders of the Golden Wood against the forces of Moria and Dol Guldur. They also had the role of scouts in Lorien. They wore grey hooded cloaks.
Haldir of Lórien and his company encountered the The Fellowship of the Ring when the latter entered Lothlórien. After talking with the Fellowship about the conditions for entering the realm; they led them blindfolded to the Lord and Lady of Lothlórien.
Portrayal in adaptations
Peter Jackson's The Fellowship of the Ring
In The Fellowship of the Ring, a group of archers led by Haldir ambush and question the Eight Walkers, allowing them to enter their land.
In the game The Lord of the Rings: The Battle for Middle-earth II, they are the basic units of the elves. They are divided in warriors, which have leather armor, one handed swords and shields similar to those used by the Ñoldor on the first film, and archers which have purple robes, leather armor and Bows of the Galadhrim. They are named Lorien Warriors and Lorien Archers in the game.