Possible Clues:

• London landmark
• Capital place where an old serviceman is always looked up to
• What the National Gallery overlooks
• London tourist attraction
• Settling into new quarters, servicemen organised gala — there's a column in that
• Where place for public hangings can be seen behind admiral's back
• Site of Nelson's Column
• Battle on the level ground near Charing Cross
• London's National Gallery is on it
• Lord Nelson statue site