In the Asparuhov area in the southern part of Varna, it’s possible to put together a decent 4-5 km run combining the road alongside Asparuhov Beach and the paths in Asparuhov Park.

Starting from the north end of the beach, do a ~2 km loop of the park’s paths. It’s not a fancy park, but it’s pleasant enough for running, with some nice green spots and a combination of interior paths & paths near the water — all very wide. Then, run along the beachfront road, ~1 km each way. There are cars, but also lots of folks walking, so it’s safe for running.

The beach itself is popular, but not great for running as it’s mainly soft sand.