I let go of my hair, grab my phone, and laugh (and apologise) as my hair hits the man behind me. “The view spans over 25 miles, covering 28 London boroughs and four counties!”It is indeed, a hair-raising experience, in more ways than one. I’m on top of Ally Pally, the 150-year palace in north London named after Princess Alexandra of Denmark. It’s London’s newest roof-top adventure and the highest roof walk in the UK (at 130 metres – or 426ft – above sea level). Summit offers three ticket options: daytime climbs, sunset climbs and London lights climbs (after dark).