Denham Roundabout

Denham Roundabout is junction 1 of the M40.

Originally the end of the Western Avenue, when the M40 came, this junction between Uxbridge and Denham was rebuilt with a very big roundabout because the ringways plans planned for a large number of slip roads potentially meeting it. The large radius meant fast circulating speeds, and a high accident rate, so it was turned into a Magic Gyratory.

Routes

Route	To	Notes
M40	Birmingham, Oxford, Beaconsfield, Heathrow Airport, Watford (M25)
A40	Amersham, Gerrards Cross, Denham, Rickmansworth (A412)	Amersham via A413
A40	C. London, Harrow
A412	Slough, Iver Heath
A4020	Uxbridge, New Denham
	Denham Court	tourist signs to Buckinghamshire Golf Club, Denham Country Park, Colne Valley Park Centre and Groundwork Trust
A40(M)	Oxford, Beaconsfield, High Wycombe
A403	London, Northolt
Northern and Western Motorway	The NORTH	unbuilt early motorway plan.
Denham Spur	The NORTH, Watford, Stansted Airport, (M1, A1(M), M11), Pinner, Bushey (M16)
M25	Aylesbury, Hemel Hempstead (A41(M)), Rickmansworth, Maple Cross	possible routing via this junction
M25	(M4, M3, M23), Heathrow Airport, Staines, Gatwick Airport	possible routing via this junction