Beginner at the moment the closest to me are bunker 51 and red 1 Chislehurst. Anyone know any close sites near me, there are some sites that are not listed on airsoft map.
I wouldnt bother with bunker, or Tactical warfare. Plenty of decent sites up Essex way, and some into Kent as mentioned though a Car or transport is needed. Not many options if you need to use public transport.
Have a look through here at the SE Tour reviews from @Asomodai because he has done all the hard work for you and I have personally yet to disagree with any of his points on any of the sites we have both been too.