You can easily reach within a,
1-5 min walk: Covent Garden Piazza and Flower Market, Opera House, Theatreland, Leicester Square.
5-10 min walk: Trafalgar Square, SOHO, Piccadilly Circus, St James, Regent Street.
10-20 min walk: Mayfair, Oxford Street, Bond Street, Green park and Hyde park, Buckingham Palace, River Thames and Embankment, London Eye (25min walk).