To reduce the risk of head-on collisions, the Kansas Turnpike now has a continuous, permanent Jersey barrier in the median over its entire length. On opening, there was no fixed speed limit on the highway; drivers were merely asked to keep to a "reasonable and proper" limit, although shortly afterward signs were erected in certain stretches indicating a maximum speed of 80 miles per hour (130 km/h). From 1970 to 1974 and again since 2011, the turnpike's speed limit has been set at 75 mph (120 km/h); that limit during the earlier period applied only during daytime hours.