The Chalfont Viaduct is the first of two five-arch brick railway viaducts on the Chiltern Main Line in south-east England. It is located between Gerrards Cross and Denham Golf Club stations. The M25 motorway passes beneath it between junctions 16 and 17 at Gerrards Cross near Chalfont St Peter, from where the bridge gets its name. The bridge is known as Chalfont No. 1 Viaduct; the longer Chalfont No. 2 Viaduct is a short distance to the west and spans the A413.
Chalfont Viaduct seen from the M25 (in 2009)
The River Misbourne diverted via culverts under the M25
The new "give helch a break!!!" graffiti slogan added in 2018
The "helta▪skelta" graffiti slogan, which first appeared in 2021.
The Chiltern Main Line is a railway line which links London (Marylebone) and Birmingham on a 112-mile (180 km) route via High Wycombe, Bicester, Banbury, Leamington Spa and Solihull in England.
Chiltern Railways London to Birmingham express near Hatton, hauled by a Class 68 diesel locomotive.
Ex-GWR King Class locomotive 6008 King James II hauling a Paddington to Birkenhead Woodside express in 1950
Class 52 hauling an express from Paddington to Birkenhead Woodside near Seer Green in 1962
Class 115 DMUs operated Marylebone - Banbury local services between 1960 and 1992
