Afterhours behind Sonar...

2 years ago I went to Palladium and we got this flyer for an after hours...and it was behind the Sonar..in the back alley..well not right behind Sonar..but a bit down ...
You walk through these jail like fences , pay and go inside, down this hallway...it was like a house inside.
There was skylights on the roof ..it was so cool.
Ever since then though, I've never heard of another afterhours there...

When we left , you go out this door and it takes you right to the main street where the front door of Sonar is...broad daylight...satruday morning @ 6 am with working people walking everywhere...and your all sketchy and in the daylight all of a sudden from being inside this dark black lighted room.

it was pretty weird.
But has anyone ever been to that place????
Does it still go off?
Where is a really good after hours now a days?