Doctor Who has now been lighting up our screens for over 51 years which means that it's got a whole lot of legacy behind it. Throughout his ongoing universal escapades, TV's favourite Time Lord hasn't just been changing and saving history, he's often been making it, too. With over 800 episodes and counting to its reputable name, the franchise has firmly established itself as a formidable cultural phenomenon and it's even breaking ratings records around the world with an ever growing global audience of 70 million viewers. Not too shabby for a show that all started out as a mild curiosity in a junkyard, eh? Of course, such a voluptuous track record of timey-wimey shenanigans means that there are plenty of memorable moments to pick out from its momentous mythology. Doctor Who fans are hardly stuck for choice when it comes to choosing their 'best bits' but, every now and then, somethings happens that manages to break out from the coveted confines of fandom appreciation to affirm its presence as a piece of groundbreaking drama in the history of television itself. Here are 20 of the most iconic Doctor Who images and moments of all time, because you don't need a TARDIS to embark on a trip down memory lane...