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CrashStats

Serious A414 crash in Dacorum on 25 October 2025 at 20:05 involving a Mercedes A Class

A Mercedes A Class and a car were involved in a crash on the A414 in Dacorum at 20:05 on Saturday 25 October 2025. A 19-year-old female passenger in the Mercedes A Class was seriously injured and the 19-year-old female driver of the Mercedes A Class was slightly injured.

It happened after dark under street lighting on a wet roundabout with a 40 mph limit.

Severity
Serious
Date
25 Oct 2025
Saturday, 20:05
Vehicles
2
Mercedes A Class and car
Casualties
2
1 seriously injured, 1 slightly injured

Location of the crash

Police recorded the crash at latitude 51.74935, longitude -0.45077, in the HP3 postcode district and within the built-up area of Hemel Hempstead. It is one of the crashes that make up the Adeyfield West, Dacorum, HP2 4BH area accident hotspot.

Map of where the crash happened in Dacorum

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  • 1 crash
  • Serious

Collision details

Basic information

Reference
2025411659728
Council area
Dacorum
Police force
Hertfordshire
Police attended the scene
No, reported using a self completion form
Highway authority
Hertfordshire

Road and location details

First road class
A
First road number
414
Road type
Roundabout
Speed limit
40 mph
Urban or rural
Urban
Trunk road
Non-trunk road

Junction information

Junction type
Not at junction or within 20 metres

Pedestrian crossing information

Crossing facilities
Pedestrian phase at traffic signal

Environmental conditions

Light conditions
Dark, street lights lit
Weather
Other
Road surface
Wet or damp

Enhanced collision data

Serious injury band
Less serious
How severity was recorded
From injuries recorded by police (CRASH system)
Estimated chance it was serious
100%
Estimated chance it was slight
0%

The 6 nearest recorded crashes

The nearest, 2 metres away, was a slight injury crash on 22 October 2017.

Vehicles involved (2)

  • Vehicle 1: Mercedes A Class

    Car

    Manoeuvre
    Overtaking stationary vehicle on its offside
    Position at junction
    Not at or within 20 metres of junction
    First point of impact
    Nearside
    Left-hand drive
    No
    Journey purpose
    Personal business or leisure
    Driver sex
    Female
    Driver age
    19 years
    Engine capacity
    1,332 cc
    Fuel or propulsion
    Petrol
    Driver home area deprivation
    20 to 30% least deprived
    Distance from driver's home
    10 to 20 km

  • Vehicle 2: Car

    Position at junction
    Not at or within 20 metres of junction
    Driver sex
    Female

Casualties (2)

  • Casualty 1: Driver

    Slight

    Female, aged 19, car occupant, in vehicle 1 (Mercedes A Class)

    Home area deprivation
    20 to 30% least deprived
    Distance from home
    10 to 20 km

  • Casualty 2: Passenger

    Serious

    Female, aged 19, car occupant, in vehicle 1 (Mercedes A Class)

    Car passenger
    Front seat passenger
    Serious injury band
    Less serious
    Home area deprivation
    10 to 20% least deprived
    Distance from home
    20 to 100 km

Data source

This record comes from the Department for Transport’s road safety data (STATS19), in which police forces in Great Britain record every road crash reported to them where someone was injured. It is reference 2025411659728 in the data published on GOV.UK under the Open Government Licence v3.0, and one of the crashes counted in the Dacorum road accident statistics for 2025.