|Location Map ( geo)|
|Via:||Marsh Barton Industrial Estate|
|Distance:||1.5 miles (2.4 km)|
|Route outline (key)|
The B3123 is a local route through modern industrial and retail estates in the south of Exeter. It starts on the A377 and runs into Alphington, then heads left to pass through the Marsh Barton Trading Estate until meeting the A379 at Marton Bridge.
The B3123 was mostly purpose built, but the northern section is on the original alignment of the A38, which became the A3085 when the Exeter Bypass opened. It was downgraded when the M5 was completed in the area.