The only way to visit this site was on an organized tour. Photo identification was required and bags were searched as if we were possible terrorists before we headed out with a guide who read off a set script. I’m not sure why the search was necessary because we were only ushered through about an eighth of the grounds and weren’t allowed inside the palace.
To make the tour even worse, when I took a photo I was scolded by the guard who ushered the group along like a heard of cattle. The ever-present paranoia of the guard on the tour must have been due to Tokyo’s near annihilation during WWII because most of the city’s buildings dated from after the war and the palace was one of the few remaining ancient sites. We spent most of the time outside at what I believe was the newest and most ugliest building.
My advice is if you’re heading to Kyoto that escaped the bombing, don’t waste time on this Tokyo tour. Visit Kyoto’s Ninjo Castle instead where you’ll be able to stroll at your own pace along marked pathways and even enter inside the palace to view the beautiful interior rooms. Although Tokyo’s Imperial Palace tour was free, it’s better to pay the 500 yen in Kyoto and actually see something. See my post on Ninjo Castle: https://malleestanley.wordpress.com/2018/10/12/kyotos-ninomaru-goten-palace/