It depends upon which direction you are staying in Bangalore
If you are from South Bangalore (areas like Electronic City, Bommasandra, Koramangala then
1. the nearest Beach from Bangalore would be Promenade Beach, in Pondicherry, just 6 hr 17 min, 317 km distance around,
Famous for massive of bowled us and same views it becomes a peaceful, vehicle free pedestrian zone in the evening, offering a perfect spot for sunset strolls seaside cafes and historical sightseeing
2. Next is Muzhappilangad Drive In Beach, in Kannur Northern Kerala
From Bangalore it's just 6hr 29 min and 318 km.
This is one of the unique beach where you can drive in beach for experience,
Asia’s longest drive-in beach and the only one of its kind in India. Located on the Malabar Coast in Kerala, 4-kilometer stretch of sand right beside the waves, known for The Shoreline Drive Adventure Sports, Birdwatching, local Culture & Cuisine:
3. However in Karnataka Tannirbhavi beach in Mangalore is the nearest one..which takes 6–7 hours, 363 km,
And Panambur Beach
Suratkal Beach
Only disadvantage is Time consuming route, ghat Section near Sakleshpur several road work is going on, Monsoon Season landslide issue happen
4. In Tamilnadu, the nearest beach is Marina Beach in Chennai which is 6hr 50min and 352 km
Disadvantage is on weekends very crowded, located at Anna Square Chennai,
Here horse/camel ride also available, must try for kids and food explore.
However there are 3 more beaches in Chennai
Edward Elliots Beach
ECR Beach
Kovalam Beach
5. If you are from North Bangalore, Near Devanahalli, Yelahanka, Near Airport then
Ñ4 beach in Northern Chennai is the nearest beach from Bangalore
Much Calm and quieter than Marina Beach..where you can enjoy weekend without any rush.
Hardly anyone talks about this beach, must visit destination.
N4 Beach is known for fishing harbour, good sunset photography,
This spot is located near Tondiarpet in Chennai.
Next spot is Ennore Beach.
So overall on paper, Pondicherry is much nearer than Chennai and Mangalore.
With good quality road fully 6-lane Highway drive via Hosur Krishnagiri, Vellore then Chennai is the best option.