North of the M25, the road is a near motorway standard "A" road with all junctions grade-separated via underpasses or flyovers, but curves and gradients a little steeper.
There are no hard shoulders but frequent lay-bys.
It climbs through the Chiltern Hills then descends into the valley of the River Bulbourne crossing water meadows just outside Hemel Hempstead at Boxmoor.
There are grade-separated junctions with the A414, A4251 and A416.
The route returns to open country north of here, passing west of Berkhamsted.
It passes the National Film Archive.
Before Tring, near Wigginton, it crosses the Icknield Way Path and Chiltern Way.
An arched footbridge spans the road just near the summit before it passes just east of Tring (for the Ridgeway footpath) and descends the Chiltern scarp into the Vale of Aylesbury.

The Tring bypass was built in 1973 as the first section of the Watford-Aylesbury A41(M) motorway.
 On 6 July 1987, this section was downgraded to A41.
The Tring bypass ends with the junction with the B4635, B4009 (the former route through Aston Clinton) and B488.

The A41 from junction 20 of the M25 to the Tring bypass was built in the early 1990s and opened in two sections: the 7 miles (11 km) £23.9m Berkhamsted bypass opened September 1993 and the 5 miles (8.0 km) £32.7m Kings Langley bypass opened August 1993.
North of the M25, the road is a near motorway standard "A" road with all junctions grade-separated via underpasses or flyovers, but curves and gradients a little steeper. There are no hard shoulders but frequent lay-bys. It climbs through the Chiltern Hills then descends into the valley of the River Bulbourne crossing water meadows just outside Hemel Hempstead at Boxmoor. There are grade-separated junctions with the A414, A4251 and A416. The route returns to open country north of here, passing west of Berkhamsted. It passes the National Film Archive. Before Tring, near Wigginton, it crosses the Icknield Way Path and Chiltern Way. An arched footbridge spans the road just near the summit before it passes just east of Tring (for the Ridgeway footpath) and descends the Chiltern scarp into the Vale of Aylesbury.
The Tring bypass was built in 1973 as the first section of the Watford-Aylesbury A41(M) motorway.  On 6 July 1987, this section was downgraded to A41. The Tring bypass ends with the junction with the B4635, B4009 (the former route through Aston Clinton) and B488.
The A41 from junction 20 of the M25 to the Tring bypass was built in the early 1990s and opened in two sections: the 7 miles (11 km) £23.9m Berkhamsted bypass opened September 1993 and the 5 miles (8.0 km) £32.7m Kings Langley bypass opened August 1993.
A41 road