Kras is a karst plateau that gave the name to the whole karst phenomena (that's why they also call it the Karst). The best time to visit is autumn, when the leaves, especially the leaves of the smoketree (slo.: ruj) get all kinds of crazy colors, from dark green through bright green, yellow, orange and red to dark purple that is almost black. A closer look at this can be seen in the smoketree gallery.