The romantic St James’s Park, designed by Buckingham Palace’s architect John Nash, is the oldest Royal Park in London. Hire a stripy deckchair or stroll along the lake to spot the scores of bird species there (the park’s bird keeper even lives on site, at Duck House). There’s also a great little restaurant in St James’ Park, called Inn the Park – with an outside terrace, hireable rooftop space and surprisingly good food it gets quite crowded on warm summer evenings.