Queen Elizabeth Roof Garden Bar & Café

'Contentment!' came a slightly exasperated voice, from around the next purple-painted olive tree planter overflowing with vermillion flowers. 'Contentment!!' 'CONTENTMENT!!!' The mysterious diner may have been struggling to get their point across, but there's no such confusion for most people having lunch or sipping drinks in this rooftop allotment-cum-woodland-cum-wildflower meadow. At sunny lunchtimes, you'd be hard put to find a prettier setting for a sandwich in central London – it's all tangles of nasturtiums, pergolas dripping with lilacs, boldly sprouting cabbages and an actual garden shed. Make sure you follow the walkway at the back all the way around the corner, to commune with the thickets of full-sized birch trees.

Food and drink come from a smart wooden bar area run by Company of Cooks. Don't hold out for a full meal or a fry-up, but the short menu of light salads, sandwiches, cakes and snacks suits the civilised, slightly otherworldly vibe (there's no smoking, and a cap on crowds). A salad of trout, fennel and radish came in a pre-packaged box but the ingredients were perfect – spanking fresh and at just the right temperature, brought to life by a squeeze of lemon. For a sundowner, things like wild strawberry bellinis or passion fruit mojitos available by the jug sound extremely promising. 

And did we mention the view, across rooftops and the sparkling river? And that the volunteer gardeners are part of a charity that promotes gardening as therapy? Oh fine, we'll be quiet. Just – as you leave, trail your palm across the handy thicket of rosemary planted by the head of the sunshine-yellow stairway, and take the garden scent out into the world with you. Contentment, indeed.