The Chiltern Firehouse is a hotel in Marylebone converted from an old firehouse with a beautiful outdoor terrace. There's a cozy tented area with a fireplace (pictured) as well open-air seats. You're surrounded by greenery such that you can't tell you're on a street with lots of cute shops. Vibes are more London posh - I expect you'd see some London aristocracy if you stayed long enough. There's coffee, tea, fresh juices, cocktails and non-alcoholic cocktails galore. I've been twice I like it so much. Their flat whites are beautiful foamed. Their concoction of lychee, coconut water and hojicha tea was just okay but I'm a tea snob. Wi-Fi is free and service is slow; you're meant to take your time.