Skate help

Firstly in the oldt town in that really long drainage ditch thing, just after you come out the pipes and go down that steep hill there is a fenced off area to the left with Ai skaters skating in it, how do i access it?

Secondly how far do i have to get in the game before unlocking the X games arena?

The way it is on the Xbox (And its same on ps3) Is to just keep getting cover shots and doing the goals, then you will unlock new areas and spots. Same to get the X games, if you get to the cover on one mag, the near the end of the other, or the end. Thats when I reached X Games.