An attempt at a map limits summary for de_piranesi:
CTs can go through the castle buildings but must go no further than:
On the first floor: the exit towards T-side of the archer windows area.
On the Parapet: the T side entrance onto the parapet (top floor)
There is an entrance into the Globe Bomb Site that comes from T-spawn, via the large grass area behind the parapet (the one that also leads to the back of the 2 sets of large wooden double doors). From the Globe site, CTs can only go as far down that entrance as the start of the lawned area (from where you can see the rear of the parapet and the double doors).
From the Sun Dial site CTs can cross to the opposite T-side entrance, but should not go in to the building on the T side. Likewise, CTs can enter the 2 sets of large wooden double doors but should not advance out on to the grassy area at the rear.
Otherwise, that's pretty much it for this map. And as usual, all bets are off when the bomb has been planted.....
TL. 8)
(http://www.btinternet.com/~p.d.herbert/mhpcs/2dmaps/PIRANESI.JPG)