We studied a population of Aesculapian Snakes (Zamenis longissimus) living close to a 1,000-m stretch of busy road located in northwestern Bohemia. We monitored the extent of road mortality and related behavioral characteristics. A large number of snakes regularly inhabited the road's embankment during monitoring in June and September. Some individuals were observed to stay in exactly the same spot continuously for several days. Snakes were active starting between 0800 and 0900 h in the morning and ending by 1900 h in June and 1800 h in September. Activity was greatest during the morning. The most frequent type of observed behavior was related to thermoregulation. The snakes did not react visibly to passing traffic. The Aesculapian Snakes' activity was higher, and started at lower temperatures, in June than in September. The mean body temperature of the Aesculapian Snakes was 24.3°C. On average, it was higher than the ambient air temperature until the ambient air temperature exceeded 27.8°C. We detected very little road mortality of adult snakes. Even though they used the road embankments and adjacent stone abutment walls frequently, they virtually never ventured onto the surface of the road. To cross the road they generally used the culverts under it. Juvenile snakes ventured onto the road frequently and their road mortality was high.