Throughout the Republic of Korea (ROK, South Korea) crime rates are consistently low and the country is generally a safe destination for most travelers. Due to the climate of the region, some seasonal rains can be heavy enough to temporarily block or wash out isolated sections of road. In some areas, South Korea's mountainous topography has lead to the routing of unusual road networks and interchanges. While some major road signs in South Korea are posted with English place names included, foreigners who cannot read Korean report that there are some difficulties in navigating by South Korean road signs. Drivers are aggressive, especially in the larger cities. Pedestrians should be careful of the vehicles that frequently do not yield, even in marked crosswalks. South Korea has not experienced any terrorist incidents in recent history. South Korea boasts an affordable and accessible universal healthcare system, rated by 2016 Bloomberg report as the world's fourth most efficient healcare system, after only those of Hong Kong, Singapore and Spain. In South Korea, quality healthcare is available through general hospicals, oriental hospitals (using traditional Eastern medical practices), public health centers and private hospitals. The medical facilities exist in three tiers, depending on the size and number of departments. Additionally, Korean food is very nutritious and tasty. Korean cuisine includes a variety of soup and stew dishes full of healthy ingredients, bone broth, plenty of vegetables, lean proteins, often simmered with fortifying herbs and roots.