Ranged around BBD Bagh is much of Kolkata's finest colonial architecture. Originally called Tank Square, its palm-lined central reservoir-lake ('tank') once supplied the young city's water. Some locals still use its later-colonial name Dalhousie Square commemorating British Lieutenant-Governor Lord Dalhousie. But with delicious irony, the square is now re-renamed after the nationalists who tried to assassinate him.

In fact the BBD trio (Binoy, Badal and Dinesh) bungled their 1930 raid, killing instead an unlucky prisons inspector. Nonetheless the attack was a highly symbolic moment in the self-determination struggle. The assassination took place within the photogenic 1780 Writers' Building whose glorious south façade looks something like a French provincial city hall. Originally built for clerks ('writers') of the East India Company, it's still a haven of pen-pushing bureaucracy.