The A3081 was the eastern half (from Mutley) of the former B3241 in Plymouth, gaining its number around 1930.
The road started on the original route of the A386 (now B3250) at the southern end of Mutley Plain and headed east along Alexandra Road. The road was largely straight except for a zigzag to go under the railway line. The road soon reached Laira where it ended on the original A38 (now A374) on the bank of the River Plym.
The road has since been downgraded to Class II status (probably at the same time as the A386 was moved) and is now the B3214.