GTA III and Vice City have 3DS ports, but I think they only work with New 3DS models. You can also play Chinatown Wars, Advance, and the two GBC ports on 3DS.

Oh, and the PS1 games can be played using a PS1 emulator on New 3DS.

Bob - What do you MEAN there's a GTA IIID?! Was that a R* official, or is it a community decomp?

Taeo Gta III is a port of re3 look it up it runs pretty smoothly on N3DS models