|Location Map ( geo)|
Almost as soon as you enter Cornwall from the Tamar Bridge, the A38 dives into the Saltash Tunnel. Between the two, a pair of east-facing sliproads connect to the B3271, which provides a surface alternative to the tunnel.
The tunnel is a single-bore, with three traffic lanes passing through and is part of the tidal flow system across the Tamar Bridge. It passes under a residential area to the north of Saltash Town Centre and is approximately 500m long. At the western end, a roundabout provides access to the B3271 again, with the A38 then being dualled as far as the split with the A388.