Laid back 'bare brick and sofas' bar overlooking Leicester Square, not the place you'd expect to find a chilled out crowd sipping cocktails, but Oxygen is well worth knowing about for precisely this reason.

From midday until 7pm this place is on permanent happy hour and that makes it a great bet for a liquid pit stop if you're in the West End. They also do a nice line in pricey but delicious food from fry ups to olives and bread.

As the evening wears on, DJs crank up the volume and the party kicks off, especially in the upstairs bar.