The B689 was a short link road in the Nottinghamshire town of Newark-on-Trent. It was the highest-numbered, and northernmost, 3-digit B-road in England.
The road started on the A1 (now B6326) London Road in the centre of town. It headed southwest along Portland Street and Victoria Street to end after about half a mile on the A46 Mill Gate.
The road was later upgraded to Class I status, although its short length makes it difficult to ascertain which number it received (it may have become a spur of the A46, or an out-of-zone extension of the A17). Newark has been bypassed by both the A1 and A46 and so the ex-B689 has been downgraded to Class II status again. It (along with much of the pre-bypass A46) is now part of the B6166.