Jun
I have photographed in some difficult places throughout my career ... a number of times at number 10 and 11 Downing Street where you can only imagine the security hoops you have to jump through; shopping centres and train stations are always full of applications for permits and jobsworths!; there have been some difficult countries along the way such as Liberia and north Mexico where I was escorted by a guy with an M16 rifle; and more recently at Charles de Gaulle airport which took five months of applying for permission to photograph the new Cathy Pacific Upper class and business lounge for the architect, RTKL.
Even with all the right paperwork we had a half hour discussion with the security desk about whether or not we had the correct paperwork. When we were finally allowed through I had a window of around four hours to photograph the space so had to move fast.