The Sion Panvel Expressway is a 25 km (15.5 mi) city highway serving the city of Mumbai

Mumbai

Mumbai , formerly known as Bombay in English, is the capital of the Indian state of Maharashtra. It is the most populous city in India, and the fourth most populous city in the world, with a total metropolitan area population of approximately 20.5 million...

, India

India

India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

 currently under construction. It is one of the busiest and most important roads in the Mumbai Metropolitan Area and connects the city with National Highway 4

National Highway 4 (India)

National Highway 4 is a major National Highway in Western and Southern India. NH 4 links four of the 10 most populous Indian cities - Mumbai, Pune, Bangalore and Chennai. NH 4 is in length and passes through the states of Maharashtra, Karnataka, Andhra Pradesh and Tamil Nadu.NH 4 constitutes...

. It is generally 12 lanes wide (6 lanes in each direction). The highway begins at BARC Junction Sion and stretches up to Kalamboli Junction Panvel

Panvel

Panvel is city and a municipal council in Raigad district in the state of Maharashtra. Panvel is also known as the gateway of Konkan region. It adjoins Navi Mumbai, and is just after the Thane district border. Panvel is located on the Yashwantrao Chavan Expressway about 21 kilometres from...

.