This pub was editorially chosen for inclusion by Londonist.
You can't really get more authentic than the Wickham. As soon as you step in the door, you know you're in a true community pub that values its customers. The pub's website declares that it is "proud to have served our community for over 150 years". And what a cosy, friendly place it is. Big, too, with two separate wings extending either side of the bar. One leads to a pool room (of the green baize type, not the swimmy wet type), the other takes you to an area of traditional wood and cloth banquette seating. While food and drink choice aren't exactly overflowing with options, you'll find what you need, including ale from nearby Brockley Brewery. Confounding stereotypes, you'll even pick up free wifi here. Places like this should be treasured.
Update January 2016: Lewisham Council isn't terribly happy with current management of this pub, as it keeps falling foul of its licence and patrons making a nuisance of themselves. We'll be keeping an eye on the situation.