10 Doctor Who Secrets Everyone Knows But You
7. Origins Of The TARDIS
The Doctor's trusty time machine (and occasional wife) is a big blue box that is - all together now - "bigger on the inside."
It's been there since the very start of the show, and its exterior appearance hasn't changed all that much over the years. On the inside though, it's been completely redecorated about a dozen times by now.
But what are the round things? No idea.
The story goes that the TARDIS was designed to look like a British phone box for that most reliable of reasons - budget constraints. While some sources claim the TARDIS was created specifically for Doctor Who, conflicting reports indicate that it was actually nicked from another BBC show. Z-Cars (pronounced "Zed-Cars") and Dixon of Dock Green are the prime suspects, with the latter even being cited by Steven Moffat.
The original TARDIS prop remained in use for 13 years, until it was literally falling apart. According to Elisabeth Sladen herself, it once collapsed right on top of her!
And speaking of that wonderful lady...