6th April, 1930 is well known in the history of India because this date is associated with

On April 6, 1930, Mahatma Gandhi reached the coastal village of Dandi in Gujarat and formally broke the Salt Law by picking up a lump of natural salt from the seashore. This event marked the successful culmination of the 24-day Dandi March (which began on March 12, 1930) and officially launched the nationwide Civil Disobedience Movement.