1GL Bolt: Northallerton, North Bridge   

Bolt in East face of South pier of North Bridge ; 7.55 ft. below corner of East battlement [1GL, Selby to Newcastle-upon-Tyne, Mark No. 105]; PA BOLT NE FACE BR PARA 15.6M NW LC GATE NE SIDE RD (38.5795m ODN, 1.5m AGL, 1st order).

Location
Grid reference: SE 3651 9461.
Landranger 99: Northallerton & Ripon, Pateley Bridge & Leyburn.
Structure: Bridge.
Waypoint: BT0732.

Neighbouring Bench Marks

BM	Yafforth,All Saints Church 2.09km to the west.
BOLT	Ainderby Steeple, St. Helen's Church 3.97km to the southwest.
BM	Leake Bridge 7.77km to the southeast.
BOLT	Leake, Church 7.88km to the southeast.
BM	Borrowby, Old Toll House 8.60km to the southeast.

The nearest fundamental bench mark is Northallerton, 6.34km to the east.

First Primary Levelling, England & Wales (1840-60)
This bench mark was used during the First primary levelling, England & Wales, and was levelled with a height of 126.7550 feet [38.6349 metres] above mean sea level (Liverpool datum). It was included on the Selby to Newcastle-upon-Tyne levelling line. The surveyor's description was Bolt in East face of South pier of North Bridge ; 7.55 ft. below corner of East battlement.

Third Geodetic Levelling, England & Wales (1950-68)
This bench mark was used during the Third geodetic levelling, England & Wales.