|Muggles' Guide to Harry Potter - Place|
|Number 4 Privet Drive|
|Location||Little Whinging, Surrey|
|Permanent Residents||Harry Potter, Vernon Dursley, Petunia Dursley, Dudley Dursley|
|First Appearance||Harry Potter and the Philosopher's Stone|
Number 4 Privet Drive is a thoroughly ordinary house on a thoroughly ordinary street, in the fictional suburb of Surrey called Little Whinging, where Harry Potter lives with the Dursleys, his thoroughly ordinary aunt, uncle, and cousin.
When Harry is left on the doorstep of Number 4 Privet Drive, after he is orphaned, Professor McGonagall protests, characterizing the residents as "the worst kind of Muggles." This is apparently a valid assessment; when we next see him, ten years later, Harry lives in a cupboard under the stairs. Shortly, he begins receiving letters from Hogwarts, addressed exactly to his "cupboard under the stairs". In what might be an attempt to avoid future letters being sent, or more likely a reaction to outsiders apparently knowing how Harry is being treated, Harry's aunt and uncle move him to his cousin Dudley's second bedroom, where Dudley stores his extra and broken gifts. Throughout the rest of the series, Harry retains the use of this bedroom when he is living at the Dursleys, though the broken gifts are not in evidence in Harry's second year and later; we assume they have been moved somewhere else or discarded. Harry is locked into this room at times, just as he was locked into the closet under the stairs initially, at one point even having bars installed over the window. Harry does eventually learn how to pick locks without use of magic, thus gaining limited freedom of the house for himself, despite being locked into his room, when he needs it; and he also carves out a hiding place under the floorboards of his room, where he hides gifts from Ron, Hermione, and Hagrid, and magical artifacts of one sort or another.
We hear, multiple times, that other wizards are willing to provide Harry a permanent home, taking him away from the abusive and hated Dursley family, but they are overruled by Dumbledore, who says only that he has his reasons for keeping Harry at the Dursleys'.
The ordinary, non-magical nature of the house on Privet Drive is reiterated throughout the series. It reflects the Dursleys' views on magic, that it should not be tolerated, it should not be allowed. Even the sitting room fireplace, which we see in use to burn letters addressed to Harry in the first book, has been walled up by the fourth book, and an electric fire placed in the wall where it was. We suspect that the randomness of a real wood fire is annoying for the Dursleys, though it may simply be a reaction to the letters coming down the chimney in the first book. This squared-off rigidity makes a sharp contrast with the rather amazing pile of magical construction that is The Burrow, Harry's favorite place to stay (apart, perhaps, from Hogwarts).
It is mentioned in passing that the house at Privet Drive has four bedrooms; one is for visitors (usually Uncle Vernon's sister, Marge). Initially, one of the others is for Vernon and Petunia, one is for Dudley, and the last and smallest one is for Dudley's broken and unused toys. After the first letter for Harry arrives, and it becomes obvious that someone knows that Harry has been sleeping under the stairs, Harry is moved into Dudley's second bedroom. We believe this move is only done to "keep up appearances": whoever is sending the letters needs to be made to believe that the Dursleys are not mistreating Harry.
We should note that the name of the community, Little Whinging, is more appropriate than it might seem to non-British readers. Whinging is what is known in North America as "whining," and Dudley certainly seems to do a lot of that, at least in the first book.
Harry absolutely hates the time he spends in the house on Privet Drive; he would much rather be living with wizards. However, the protection he gained from the death of his mother, when she was trying to save him from Voldemort, will remain in force only so long as there is a place that he can call home, which is owned and occupied by his own blood – in this case, Petunia, his mothers' sister. Harry is not allowed to know this until late in the series, and even when he does understand the necessity for it, his knowing it does not improve the feelings about his required presence in that house. This protection ends once he comes of age at seventeen, which happens early in Harry Potter and the Deathly Hallows; he is then equally at risk wherever he is, and so there is no need for him to return to Privet Drive ever again, for which he seems to be profoundly grateful.
One point worth speculating on is the reason that the Order of the Phoenix thought it necessary to remove the Dursley family from Privet Drive when Harry came of age. Surely, with Harry no longer in residence, the Dursley family would be of no interest to Voldemort and his minions, except perhaps as a matter of revenge. So why remove the Dursleys? Dumbledore mentions that he had strengthened the protective magic that was based on this most ancient spell, but does not go into detail. It is possible that the strengthening applied at this time is, in fact, extension of the protection provided by the spell to cover Petunia and the other members of her family, protection that will end with Harry's majority. Dumbledore likely is aware that Voldemort tends to be vengeful against those who have gotten in his way, and by being alive Petunia has protected Harry from Voldemort. Additionally, Moody and the Order expect Harry's home to be under attack as Harry leaves, and are acting to protect the Dursley family from damage caused by spells that miss their targets. We note in passing that while Harry's protection from Voldemort is extended by Voldemort's actions when re-embodying himself, that protection is unlikely to extend to Petunia.
While it would be possible to just have this house be an unexplained bastion of enforced "normality" and non-magical life, the author has actually gone the extra step to explain why Petunia has made the effort to so greatly deny any magical influence in her home life. In the first book, we hear of Petunia's jealousy of her sister Lily's magical abilities, which would seem to be almost sufficient, given what we later learn about Petunia's obsessive behaviour, notably as reflected in her nightly ritual cleaning of the kitchen. We later find, however, that Petunia had applied to be admitted to Hogwarts and had been refused. Given this rejection by the magical world, Petunia's retaliatory rejection of anything having to do with magic is absolutely and perfectly in character.