500 feet is the law in most states. So imagine 2 football or soccer fields. Or one of each!
If you are driving with your bright lights on and can see an approaching vehicle, you should turn off your bright lights immediately.
slow down and avoid looking directly into the lights of the approaching vehicle
500'
Turn off headlights and leave parking lights on.
When approaching an aircraft at night, vehicle operators should always make themselves visible to the pilot. Aircraft cannot stop suddenly and do not have great visibility.
Turn off headlights and leave parking lights on
Turn off headlights and leave parking lights on.
turn off headlights and leave parking lights on
Be considerate in using your high beams. Your headlights must be on low beam when you are within 500 feet (150 m) of an approaching vehicle, or within 200 feet (60 m) of a vehicle ahead of you, even if the vehicle ahead is in a different lane. You should also dim your lights for pedestrians approaching you. http://www.nydmv.state.ny.us/dmanual/chapter10-manual.htm (Alaska and Oregon are the same as New York - 500 feet.)
Stay 500 feet behind it if it's lights are flashing (in the U.S.)
a collision scene
Although the lights should be dipped when approaching another vehicle so they aren't bright, the best place to look would be at the edge of the road on your side; you will still be able to see most of what is on the road ahead of you, but without looking directly at the bright lights.