The Sion Panvel Expressway is a 25 km Indian highway located entirely in the state of Maharashtra, that connects Sion in Mumbai with Panvel, via Navi Mumbai. It is one of the busiest and most important roads in the Mumbai Metropolitan Region (MMR) and connects Mumbai with the city of Pune. The National Highway 4 and Mumbai-Pune Expressway begin at the eastern end of the expressway, at Kalamboli junction, near Panvel. The highway is also used by vehicles traveling towards Mumbai from Konkan and Goa.