Not the most exciting place inside, but a lovely rooftop area which not all that many people seem to know about, 2 mins walk from Old St station. If it’s packed then The Red Lion is just up the road.
Appreciate the 'bar hidden away behind a bookcase' thing is pretty naff but the cocktails here are unreal (try the Hot and Cold), and it's inside Milroy's Soho, one of the most legendary spirits stores in the city
You could call me biased, given this is the 3rd Highbury restaurant in my list, but if you're doing so then you've clearly never tried the Biang Biang Noodles at this unassuming little BYOB gem