Clumber Park Secure Cycle Lock Up

Tomorrow

My husband and I are thinking of going to Clumber Park but know there has been an issue with bikes being stolen in the past.  I see in the site directory that there is secuire lock up.  I take it that the bikes stolen are not kept in here?  Also how is this
lock-up accessed ie do you have to ask to get your bike in and out or is there a keypad code or something similar.  Any info would be greatfully received.