The Trafalgar Square is the geographical centre of London. It was named in memory of Admiral Nelson's victory in the battle of Trafalgar in 1805. The tall Nelson's Column stands in the middle of the square. On the north side of the Trafalgar Square is the National Portrait Gallery. Not far away is the British Museum — the biggest museum in London. It contains a priceless collection of ancient manuscripts, coins, sculptures, etc, and is also famous for its library.