Greek National Road 91

Sounio, via Vouliagmeni. It was first constructed in the 1950s as a one-lane per direction road, but the section between central Athens and Varkiza was later^[when?] extended to two lanes per direction. It has many extremely dangerous curves, and accidents happen frequently.^{[citation needed]} Currently, there are no plans to replace it with a bypass or reconstruct certain dangerous parts, but there has been an effort to increase police presence to prevent illegal racing and violation of speed limits which were common phenomena over the last 10 years. The highway becomes busier during the summer, as most of the places it connects are popular vacation spots. The highway also goes past what was Ellinikon International Airport