Are muggles able to see and/or enter Hogwarts?
Has anything been said or implied in any of the books or films or any of their supporting materials that would support or conflict with Muggles being able to see or enter Hogwarts?
Are muggles able to see and/or enter Hogwarts?
Has anything been said or implied in any of the books or films or any of their supporting materials that would support or conflict with Muggles being able to see or enter Hogwarts?
Throughout the books we're repeatedly told that Muggles cannot visit Hogwarts, in its place they'd see nothing but a derelict ruin with DANGER - DO NOT ENTER signs around it. Presumably its inhabitants would also be hidden from view.
However, there's one instance - albeit only a mention - where we know for a fact that Muggles were able to go to the castle. In Chamber of Secrets, while revisiting Riddle's memory of the night Moaning Myrtle was killed, the then-headmaster Professor Dippet mentions that 'the girl's parents will arrive in the morning'.
In the film it is Riddle who says the line:
Hagrid. The dead girl's parents will be here tomorrow. The least Hogwarts can do is make sure the thing that killed their daughter is slaughtered.
We know that Myrtle is Muggle-born, her parents are Muggles. How could they visit the castle? It stands to reason that the anti-Muggle enchantments around the school can be modified to allow specific Muggles to enter, or perhaps a spell can be cast on the Muggles themselves to allow them to see through the enchantment.
Hogwarts is protected by layers and layers of charms laid by generations of wizards teaching there. So it is quite well protected by a number of them, but in this case there is one specifically designed for the purpose: Muggle-Repelling Charm
It is quite ingenious in how it works:
Every time Muggles have got anywhere near here all year, they've suddenly remembered urgent appointments and had to dash away again.
I think Hermione mentions the specific case of the charm use by Hogwarts when discussing her tent in Deathly Hallows, but this may be the memoriam fragilis est case.
There are also other charms (as mentioned in other answer), that hides Hogwarts under the illusion of desolate ruin and probably more, but Muggle-repelling charm is probably used all around the perimeter, which I assume is quite large to encompass not only castle but large area nearby, including part of the Forest (if not all, for Muggle protection).