Hogwarts School of Witchcraft and Wizardry is an ancient and mysterious institution hidden from the view of the ordinary, non-magical people known as Muggles. It is located somewhere in Scotland, but its exact location has been magically concealed for centuries. Muggles who come across the grounds of Hogwarts see something entirely different than what a witch or wizard would see.
To a Muggle, the Hogwarts grounds appear to be nothing more than ruins of an old castle. If a Muggle tries to approach the entrance to the castle, they will see a “Danger – Keep Out” sign that seems to be part of the ruins. The magical enchantments surrounding Hogwarts are so powerful that Muggles cannot see through them or bypass them in any way.
From a distance, the Hogwarts castle might look like any other historic building, such as a monastery or abbey. The Muggles would see a structure that appears to be in ruins and disrepair, with weeds and vines growing over the walls and towers. The castle’s various turrets, spires, and crenelations would be mistaken for architectural ornamentation, and the massive stone walls and ramparts would appear to be nothing more than the remnants of an ancient fortress.
The Forbidden Forest, which surrounds Hogwarts, would appear to be an ordinary forest to Muggles. They would see tall trees and dense undergrowth, but they would not be able to see any of the magical creatures that inhabit the forest. They might hear strange noises or see flashes of light, but they would assume that these were just natural phenomena.
The Quidditch Pitch would appear to be an empty field, with no sign of the magical sport that is played there. The stands would appear to be old and abandoned, and the goal posts would seem to be nothing more than tall metal poles. The Muggles would not be able to see the flying brooms or the Snitch, nor would they be able to see the players soaring through the air.
The Great Lake, which lies near the castle, would appear to be an ordinary lake to Muggles. They would see the still waters and the reflection of the sky and clouds, but they would not be able to see the giant squid or the merpeople that inhabit the lake. They might see ripples on the surface of the water or hear strange noises, but they would assume that these were caused by fish or birds.
The Hogwarts Express, the magical train that transports students to and from the school, would appear to be an ordinary steam train to Muggles. They would see the train moving along the tracks, but they would not be able to see Platform Nine and Three-Quarters or the wizards and witches boarding the train. The train would simply disappear as it entered the magical barrier that separates the Muggle world from the wizarding world.
In conclusion, to a Muggle, Hogwarts appears to be nothing more than a ruined castle with dangerous warning signs. The magical enchantments surrounding the school are so powerful that Muggles cannot see through them or bypass them in any way. While witches and wizards see a magical and wondrous world, Muggles are completely unaware of the magical happenings at Hogwarts School of Witchcraft and Wizardry.