Where's The Door?

While I was cycling to work this morning I saw some workmen erecting this shed like structure around the Robin Hood statue, close to the Castle. Some of you maybe thinking it's a publicity stunt, or some student prank or new art installation. Well you're all wrong. It is in fact protecting the stature from possible damage by demonstrators tomorrow. There are going to be several demonstrations by various political factions all happening at the same time. Then there is going to be a parade of soldiers returning from Afghanistan and a big football match. Hundreds of police are being drafted in and roads have been closed. I'm planning to go along and capture the events. I'm hoping in a way that there is going to be a riot, so I can capture some dynamic moments.