Multiple console rooms
Some of my favorite explorations of the TARDIS are the ones that feature journeys to different console rooms, both new and familiar. For example, while short, The Masque of Mandragora has one of my favorite TARDIS scenes. It features the Fourth Doctor and Sarah Jane exploring the TARDIS, finally giving us an impression of how large the inside of the ship truly is.
After a quick look at the “boot cupboard” - which is of course a nicely decorated living room - they find the secondary control room. With its wood-paneled walls and console, it’s a radically different look for the TARDIS, one that becomes the main console room for the rest of the season.
It’s a great little scene, but it also introduces a simple but rather brilliant idea - the TARDIS contains multiple console rooms, and any of them can be used as the main one. It’s a great indication of just how flexible the TARDIS’s architecture can be and a reminder of just how special and even magical our favorite time machine really is.
Going back to the New Series, it’s an idea that’s expanded on many years later in Matt Smith's episode The Doctor’s Wife. When the powerful entity House possesses the TARDIS, what’s usually magical and safe is transformed into something dangerous and horrific.
But while it provides us with a deeper (if darker) look at the TARDIS’s corridors, it also sees the return of the console room seen in Christopher Eccleston’s and David Tennant’s seasons. Again, it’s a reminder that sometimes, the TARDIS console rooms aren’t simply destroyed, but stored. Even more interesting is the TARDIS's claim that they have archived all the console rooms - even the future ones!