|This may well be the hardest dungeon to get into in the game...Caer Sidi is up there with it. But Caer's problem is being so far away, while CC is just plain tough. Hordes of 60+ mobs to just get to the entrance, then even more inside...then entrance is inside Avalon City, through a downwards passage near the center of the town. You'll know you're close when the guards are the Xar race...
Per the 1.101 Release Notes 02.24.10:
Certain zones are now flagged as Epic Zones. These zones now relocate anyone logged out for more than 30 minutes to a safe spot typically located at the start of the zone, except for the main Realm Dragon zones. The locations for these Epic Zones place you safely outside the Faction towns, near the bindstones. Per this note, Avalon City (and the Crystal Cave) is now considered an Epic Zone.