Question: The Three Rivers district, including towns such as Abbots Langley, is in which English county?

Context paragraphs:
Mill End, Rickmansworth: Mill End is a semi-rural village in Hertfordshire, England, which has in recent times become a contiguous part of Rickmansworth.  Most of it is unparished (i.e. it does not have a civil parish council); part comes under Chorleywood Parish Council.  By the time 0f the 2011 Census a new civil parish had been formed called Maple Cross and Mill End.  All of Mill End forms part of Three Rivers District and so is administered by Three Rivers District Council and Hertfordshire County Council.

Hunton Bridge: Hunton Bridge is a small settlement near Abbots Langley, Hertfordshire, England, with a historic royal connection.  Its population in the 1991 census was 327.  It is in the Three Rivers population of Langleybury.

Three Rivers District Council: Three Rivers District Council is the local authority for the Three Rivers non-metropolitan district of England, the United Kingdom.  Three Rivers is located in the south-west of Hertfordshire, in the East of England region.  The Council itself is based in Rickmansworth, the largest settlement in the district, but also comprises Abbots Langley, Chorleywood, Croxley Green, Maple Cross, Mill End, Sarratt and South Oxhey.

Bedmond: Bedmond is a village in the Three Rivers district of the English ceremonial county of Hertfordshire.  It is located around 1 mile north of the larger village of Abbots Langley.  Bedmond belongs to the civil parish of Abbots Langley and at the time of the 2011 Census, its population was included in Abbots Langley's population figures.

Three Rivers District Council election, 2012: Elections to Three Rivers District Council were held on 3 May 2012 to elect one-third of the council of Three Rivers district in England.

Three Rivers District (VHSL): The A Three Rivers District is a high school conference of the Virginia High School League which draws most of its members from the New River Valley.  The lone exception is Glenvar High School, which is located in western Roanoke County.  The district is named for the New River, Roanoke River, and Little River.  The schools in the Three Rivers District compete in A Region C with the schools of the A Hogoheegee District, the A Mountain Empire District and the A Pioneer District.

Three Rivers District Council election, 2014: The 2014 Three Rivers District Council election took place on 22 May 2014 to elect members of Three Rivers District Council in England.  This was on the same day as other local elections.

Bedmond and Primrose Hill: Bedmond and Primrose Hill is a ward in Three Rivers, in England, the United Kingdom.  It is located in south-west Hertfordshire, in the East of England region.  The ward includes Bedmond and a sparsely populated area to the north.  It lies north of the M25 motorway, which separates the ward from Abbots Langley, and is bordered by Kings Langley to the west, and Hemel Hempstead to the north.  Slightly to the east of the ward is the M1 motorway.

Abbots Langley: Abbots Langley is a large village and civil parish in the English county of Hertfordshire.  It is an old settlement and is mentioned (under the name of Langelai) in the Domesday Book.  Economically the village is closely linked to Watford and was formerly part of the Watford Rural District.  Since 1974 it has been included in the Three Rivers district.

Leavesden, Hertfordshire: Leavesden is a residential and commercial area in Hertfordshire, England, contiguous with the northern suburbs of Watford.  It lies within the M25 Motorway.  On its eastern side it is bounded by the M1 Motorway.  Leavesden is part of Abbots Langley civil parish and is also the name of a district council ward in Three Rivers District.  Leavesden Green is an adjoining residential community which lies partly in Three Rivers and partly in the Borough of Watford.

Supporting paragraphs: Three Rivers District Council Abbots Langley
Answer: Hertfordshire