Which lane is for which direction of traffic depends on what country the street is located in. On broader two-way streets, there is often a "centre line" marked down the middle of the street separating those lanes on which vehicular traffic goes in one direction from other lanes in which traffic goes in the opposite direction. Occasionally, there may be a median strip separating lanes of opposing traffic. If there is more than one lane going in one direction on a main street, these lanes may be separated by intermittent "lane lines", marked on the street pavement. Side streets often do not have centre lines or lane lines.