There are several ways to reach at campus of Bhabha Atomic Research Centre (BARC). Here I am providing instructions to reach at campus of Bhabha Atomic Research Centre (BARC):

Reach at Bhabha Atomic Research Centre (BARC)

Entry points from the Mumbai city
From the Chhatrapati Shivaji International Airport (Sahar) and Chhatrapati Shivaji Domestic Airports (Santacruz)
From Railway Chhatrapati Shivaji Terminal (CST/VT) (Central Railway)
From Railway Dadar Terminal (Central/Western Railway)
From Railway Terminal Kurla(Central Railway)
From Railway Terminal Mumbai Central(Western Railway)
From Railway Terminal Bandra (Western Railway)
From Railway Chhatrapati Shivaji Terminal (CST/VT) (Via Express Free Way)

From the Chhatrapati Shivaji International Airport (Sahar) and Chhatrapati Shivaji Domestic Airports (Santacruz)
You may take a pre-paid taxi to Anushakti Nagar. The approximate distance is 25 km and the fare is about Rs. 250/-. It is always advisable to take a pre-paid taxi from the Domestic/ International Airport.

From Railway Chhatrapati Shivaji Terminal (CST/VT)
Buy a suburban train ticket (1st class or 2nd class) to Mankhurd railway station and board the suburban train (Central Railway Harbor Line) marked M, VA, BR, KD or PL. The journey time is approximately 55 minutes.

Alight at the Mankhurd railway station and come out of the station on the east side (Platform No. 2 side).
Take an auto-rickshaw (three-wheeler) to BARC North Gate.

From Railway Dadar Terminal
If you alight at Dadar Terminus/local station (both are adjacent to each other)
You may directly take a taxi to Anushakti Nagar or BARC North Gate. The taxi fare will be about Rs.120/-. It is not advisable to take the suburban train from Dadar (Central Railway Main Line) in the evening after 3pm, especially on a working day.

From Lokmanya Tilak (Kurla) Railway Terminus (Central Railway)
If you alight at Kurla Terminus, you may take an auto-rickshaw (three-wheeler) to Anushakti Nagar or BARC North Gate. Auto fare will be about Rs. 50/-.

From Railway Terminal Mumbai Central (Western Railway)
If you alight at Mumbai Central /local station (both are adjacent to each other)
You may directly take a taxi to Anushakti Nagar or BARC North Gate. The taxi fare will be about Rs. 250/-.

From Railway Terminal Bandra (Western Railway)
You may directly take a taxi to Anushakti Nagar or BARC North Gate. The taxi fare will be about Rs. 150/-. I

From Railway Chhatrapati Shivaji Terminal (CST/VT) (Via Express Free Way)
Alight at Harbor side (platform No. 18 side) of Chhatrapati Shivaji Terminus (CST) formally known as Victoria Terminus (VT)and take a taxi to Anushakti Nagar or BARC North Gate. The taxi fare will be about Rs. 200/-. It is about 20 Km drive and will take about 25-35 minutes.