Driving on roads with no marked lanes

Roads with a single lane are likely to be narrow rural roads. You could meet all kinds of vehicles on these from small cars up to large agricultural machinery, and for this reason you should give yourself as much of a buffer as possible. 

At night it is much easier to see if other vehicles are coming because you will see the light from their headlights. In the day, though, another vehicle could be just around the next corner. For this reason, you must adjust your speed so that you can stop in half the distance you can see in front of you. The vehicle coming towards should also be able to do the same, so if you do meet and both have to do an emergency stop you should both be able to stop without having a collision.

If you are going too fast and can't stop you will end up running one or more of your wheels off the road surface where it could cause an accident because there's a slope, or large rocks or a soft surface or a slippery surface. Also, the closer you get to the edge of the road, the more likely it is to have gravel, dirt, lichen and other factors that can reduce the grip, especially in the wet. Check this article out for information on how to brake or steer if you are in this situation.