Gandhi's statue is in Tavistock Square, just south of Euston Station, London. It's regularly bedecked with flowers and garlands.
The Round Table sequence was shot in King Charles Street in Whitehall, where the Colonial Office was once based (it's now the FCO).
Kingsley Hall, where Gandhi stayed whilst he was in London, is on Powis Road, just west of Bromley-by-Bow tube. It's now a community centre. It has had an interesting history. In the 1960s it was home to a radical commune led by the 'anti-psychiatrist' R.D. Laing.