Upon first glance, Doctor Who's TARDIS isn't really anything to write home about. It's an approximation of an old London police call box that has retained relatively the same look due to a malfunctioning chameleon circuit which prevents it from blending into its surroundings. This story mechanic was designed largely to skirt budget concerns, but it's since gone on to become one of the key ingredients of the show, and an iconic piece of pop culture.

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Most people focus primarily on the TARDIS interior which changes routinely depending on the preferences of each new Doctor that comes and goes. On the outside however, a lot of change has taken place over the 55+ years. The following is a visual breakdown of how the TARDIS has made some aesthetic alterations along the way.

The Original, You Might Say

Before comparing TARDIS exteriors, it's best to lay down a point of reference. The above picture represents an actual police box based on the original Gilbert MacKenzie Trench design from the late 1920's. For years, it served as a valuable commodity for police, but few could predict just how big an icon it would turn out to be.

A popular misconception among Whovians (and Brits, for that matter) is that the original police box was made out of wood. Even the Doctor makes reference to this in the show in several episodes. Interestingly, the original design notes revealed that it was made from pre-cast concrete, which would have required more elbow grease from the Weeping Angels in order to tip it.

The Hartnell TARDIS

The original TARDIS from the William Hartnell era was quite different in many respects from the real thing. It was a bit shorter than usual, and its sloped roof ascended at a far less high angle. Dimension-wise, it was a mini variant of the actual police box, but it did come pretty close to approximating the real deal.

The rooftop light was far skinnier than the more bulbous one seen on an actual police box, but the designers managed to check off most of the other boxes, including the St. John Ambulance logo, the left door instruction panel and the overall shape of the windows. Not perfect, but certainly not bad.

The Season 4 TARDIS

For some reason, the designers modified the TARDIS for the original series' fourth season by reducing its overall height and further reducing the angled slope of the roof. It was the beginning of a few changes that stuck out like a sore thumb for all the wrong reasons.

Regardless, it was difficult to tell the differences of the TARDIS designs at this point in history, given the technical limitations of early black and white television and less-than-stellar video recording technology of the time.

The Season 5 TARDIS

In 1967, the designers meddled with the look of the TARDIS once again by slapping the instructional panel on the right door, rather than the left. This glaring oversight would be corrected in Season 6, and would also gain two door handles in addition to a keyhole swap to the right door.

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It's hard to understand the logic of the producers who commissioned this particular TARDIS , especially since it flew in the face of the TARDIS designs that came before, not to mention the real thing.

The Season 9 TARDIS

The doctored (no pun intended) TARDIS would go on to serve as the principal prop well into the Third Doctor's era, but by then it was showing signs of advance age and wear. It was repainted bright blue for season nine in an effort to offset the cruddy look which became quite apparent as the series transitioned from black and white to color TV.

This was the right call, as the showrunners could no longer hide behind black and white when it came to settings and props. Color would go on to become a major focus of the Doctor Who serials, most notably when it came to the Doctor's wardrobe.

The Season 14 TARDIS

Time had finally run out for the refurbished TARDIS when Season 14 rolled around, and it was time to put it out to grass. Doctor Who prop designer Barry Newbery (who had been with the series since the very beginning) created a brand new upgraded TARDIS from scratch.

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In terms of comparison, Newbery's Tardis was the least "lore-friendly" version ever to grace the screen. It eliminated virtually all of the rooftop slant, while further reducing the overall height of the TARDIS by almost 20% of the real police box it was based on. Lots of aesthetic changes took place here as well, including the removal of the St. John's Ambulance logo and a slight reversion to the classic instruction panel. It would serve as the primary TARDIS design for Tom Baker's early tenure as the Fourth Doctor.

The Yardley-Jones TARDIS

Four years after the creation of the new model, Tom Yardley-Jones chucked it at the request of producer John-Nathan Turner and built a new fiberglass prop. This TARDIS was a major departure from the ones that came before it, being the first to edge the design closer to the real thing.

Though the slope of the roof wasn't quite as extreme, it was far taller than previous iterations which went a long way towards representing the actual police box. Its rooftop light didn't quite hit the mark, but it did share accurate proportions with the real world equivalent. In Season 20, the prop was repainted from a bright blue to a grayish navy blue that didn't stand out so much.

The TV Movie TARDIS

After its abrupt cancellation in 1989, Doctor Who would be mothballed until 1996 when a TV movie was produced starring Paul McGann as the Eighth Doctor. To commemorate the event, producer Philip Segal ordered the construction of a TARDIS prop that was nearly identical to William Hartnell's original Tardis from Season 1, sans a few aesthetic elements. The St. John Ambulance logo was still missing, but the overall shape and width of the TARDIS was practically spot on, right down to the rooftop light.

This Tardis chucked out all previous designs in favor of a return to form, and it would have a long-lasting impact on Doctor Who as plans for a revival started to move forward.

The Rebooted 2005 TARDIS

When Doctor Who made a triumphant return in 2005, many fans wondered if their beloved TARDIS would see massive change. It never happened. In fact, the reboot's Tardis was nearly identical to the prop design used in the 1996 movie, but with a few key differences.

First, it was taller than any previous TARDIS seen before, with the right dimensions to closely approximate a real police box. Second, it sported the sharpest angle of any roof, which was almost on par with the real thing. The only noticeable deviation seemed to be the rooftop light, which was the thinnest of any seen previously.

The Latter-Day TARDIS

This TARDIS would also see a few changes throughout the new series, including the re-addition of the St. John Ambulance logo on the right side door. This seemed to run parallel to the classic series' penchant for fiddling with the design as the years went by, but to better effect.

The 2017 episode "Twice Upon A Time" provided a clever excuse for the First and Twelfth Doctors to compare TARDIS designs, with the former mentioning its increased size and the latter responding with a quip about being "bigger on the inside," eventually having an effect on the outside.

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