BS_293_2020 Zone 293. Roundabout on the road I-5. This intersection is one of the busiest danger zones in the country for many years. Historically, this intersection, together with the entire thirteen-kilometer section of road I-5 from Byala Station to the junction for the town of Borovo (the intersection with road 5101) are some of the most problematic and with the highest concentration of severe accidents in the last 30 years. This necessitated the rehabilitation of the intersection in 2010, which slightly improved the road conditions, but still this dangerous area remains active. The statistics for the last few years at this place are as follows: Year Number of accidents 2014 59 2015 56 2016 61 2017 45 2018 23 2019 (to 01.08) 16 Table 1. Statistics for the number of accidents at a roundabout, road I-5- Byala. Statistics show that the number of accidents has decreased in the last three years. Our analysis showed that this is mainly due to the preventive measures taken by the employees of the Police Regional Office - Byala, and not to the improved road conditions after the rehabilitation of the roundabout. The main reasons for many accidents to continue to occur at this point are the following: Specific implementation of the intersection. The horizontal plane of the roundabout and the inclusions of the two road sections of road I-5 to it do not coincide, especially the inclusion of the road from Byala Station in the roundabout. The bridge over the Yantra River does not allow changes to be made in it, and the circular traffic itself is not low enough and a hump is formed in the line of contact. This change in the vertical plane causes the vehicle to "lighten up" and the traction to the asphalt to be broken just as it enters the roundabout. This only matters when entering it at a higher speed. At this point, a turn is required to achieve the inclusion, which further aggravates the situation and disrupts stability. The situation of the opposite inclusion (the inclusion of the lane in the direction of Ruse-Pleven) is the same, although slightly less pronounced and of the opposite magnitude. However, there is a more significant load on the brakes (especially on the brakes of trucks) due to the large longitudinal slope of the road and the long descent during the last 6-7 kilometers, which in turn is the reason for the higher switching speed, as well as the hotter and loaded truck brakes, especially larger and heavier ones. All these factors in most cases do not lead to an accident, but the analysis of accidents that have occurred in recent years shows that the presence of vehicles in the roundabout at the time of inclusion causes distraction of drivers and "set" the above factors. receives either high-speed entry and loss of control or an accident between two vehicles due to inability to stop and subsequent withdrawal of an advantage. Specific microclimate. In the immediate vicinity of the roundabout flows the Yantra River, which (especially during the cold months of the year) is the cause of higher humidity, which is often the reason for moistening the road surface. In the winter months, this moisture often turns into black ice - an invisible thin layer of ice with great smoothness and invisible to drivers. Another climatic feature is that the circular movement is "dug" into the terrain and it is there that a specific microclimate is created, in which the air currents are weaker and cannot disperse the vapors from the river. Fog forms and they further increase the risk of a catastrophe due to reduced visibility. Volume and structure of traffic. Road I-5 is crossed by a significant number of lorries traveling to or from the Danube Bridge, which is the only bridge over the Danube in this part of the country. This leads to a high risk load of this junction with international transit freight. Many truck drivers do not pass either rarely or for the first time at this intersection and do not know its specifics and the already mentioned risk factors. More than a third of the accidents involved trucks, and almost half of them were due to loss of control of the vehicle when it was included in the roundabout. During the summer months, there is an increase in traffic with buses and cars with Romanian tourists traveling to and from Greece. They do not know the intersection, have low road discipline and very often drive too fast. Another important factor is that returning Romanian tourists are already at the end of their route - only 50 km from the Danube Bridge and 200 km from Bucharest. This makes them hurry and this is evident in the large number of speeding certificates issued by the employees of the Byala Regional Police Department in this section.