motorway markings

[regulators]

when on the motorway and you pass a sign which says e g nottingham 44 miles where in nottingham is the measured 44 miles to and also on our main roads i have seen a lot of white square paint marks on the tarmac what are these for

[sddsddean]

If you mean by white squares, a pair of squares about 4" x 4", or sometimes a pair of white circles or a pair of square silver roadstuds (like at zebra crossings), they are called 'node points'. The are used in highway maintainence to identify sections of road for maintainence gangs.
As to where distances are measured to in Nottingham, it will be some central building or feature. How about the Castle?

[jimmyb01]

It is always measured to the centre of the town or city, EG, Juction 2 of the M1 says London 14 miles when infact you have entered London at Juntion 4.

[Philtaz]

Don't know about those but in our area the squares are used by police traffic cars to measure your speed between the squares, they are usually sited near a bridge where the patrol cars park up.

[sddsddean]

No they are not Philtaz. Its an 'urban myth'. Police speed trap gear is too sopisticated to need a mark on the road. If the police do need a mark, they use something much more visible for the video camera; a bridge or a signpost. The white squares are only used in connection with road maintainence.