Hinterland is a clothing brand in Grand Theft Auto IV. The player, as Niko Bellic, can purchase the Hinterland items of clothing from the Russian Shop on Mohawk Ave in Broker. Items of clothing include jumpers, jackets and boots. Hinterland is most likely a parody of Timberland.
Posters of the Hinterland logo can be found on bus shelters and billboards around Liberty City. There is also a poster on a wall on the Hercules nightclub in Algonquin, as the building used for Hercules in The Ballad of Gay Tony was simply a Hinterland shop in GTA IV and The Lost and Damned (if The Lost and Damned is downloaded).