I have only ever been there to make deliveries, so...

I have only ever been there to make deliveries, so I'll review it for others doing the same.... You have to first go to the vehicle management office which is in the coach park, a little hard to find as it's not on the O2 site, but once you have your pass validated (stamped) it's plain sailing, just drive to the gate, they Scan your pass, and you drive in, everyone on site is really friendly but don't expect anyone to help you unload as only your contact company can do that for security reasons, but the whole experience was great! Been there six times now and never had a problem.