The Sun Calculator calculates accurate local time of sunrise, sunset, meridian passing, Sun distance, altitude and twilight, dusk and dawn times
Worth checking when you should put your Bicycle Lights on
The Road Vehicles Lighting Regulations, 1989, make the use of front and rear position lamps compulsory on vehicles during the period between sunset and sunrise.
Headlamps are required on vehicles during the hours of darkness which are defined by these regulations as being the interval between one half-hour after sunset to one half-hour before sunrise.
Lights are also required at other times when visibility is restricted.
Sunrise and sunset are defined by these regulations as local sunrise and sunset.