I'm looking for a specific type of fantasy novel.

[Chezecaek]

I'm looking for any novels that I can about characters from the real world who somehow stumble into alternate fantasy worlds. Like, say, Chronicles of Narnia or Coraline, but I'm looking for novels for adults. Anyone have any suggestions?

[Henckel]

Aside from 2 book I'm writing (both in revision stage) The cronicals of Thomas covenant come to mind. I think of them as despicable human walks onto the set of lord of the rings.

Oh, also whirlwind in a thorn tree by inde author S A Hunt. I loved loved loved those books. The third book in the series won some award a few years back.

[crlisle]

Mercedes Lackey has a series, The Bedlam Bard series, where fantasy worlds come into, mingle and threaten New York and San Francisco. My favorite is: "Spirits White As Lightning" which is the 5th book in the series. Not for children! Adults only.

[morganb]

Pretty much anything else from Neil Gaiman. American Gods or Good Omens or Neverwhere or Anansi Boys. I recommend all of them.

[Dustin Adams]

Terry Brooks Magic Kingdom for sale books were pretty great. Very light / comedic.
Not so much stumbling tho, but good nonetheless.

[disgruntledpeony]

Pretty much anything else from Neil Gaiman. American Gods or Good Omens or Neverwhere or Anansi Boys. I recommend all of them.

You beat me to it! I'll see if I can find any other options hiding on my bookshelf during the boys' next nap.

[Chezecaek]

Pretty much anything else from Neil Gaiman. American Gods or Good Omens or Neverwhere or Anansi Boys. I recommend all of them.

A lot of his stuff is close to what I'm looking for, but it's usually about a protagonist getting drawn into a bunch of weird stuff and discovering that their regular world is not quite as regular as they thought. I'm looking more for stuff where a protagonist leaves their regular world completely, temporarily or permanently, like by opening an oven and finding a portal to the magical land of the Blargalumps in the back of it or something.

[Henckel]

Definitely check out whirlwind in the thorn tree.

[Dustin Adams]

Just remembered this one:

With The Chronicles of Thomas Covenant, Stephen R. Donaldson changed the face of fantasy fiction forever. In The Mirror of Her Dreams, the astonishing first novel in the two-volume Mordant’s Need series, Donaldson shows us a world of wondrous beauty and seductive illusion, where mirrors hold the deadliest of magics and nothing is what it seems. . . .

The daughter of rich but neglectful parents, Terisa Morgan lives alone in a New York City apartment, a young woman who has grown to doubt her own existence. Surrounded by the flat reassurance of mirrors, she leads an unfulfilled life—until the night a strange man named Geraden comes crashing through one of her mirrors, on a quest to find a champion to save his kingdom of Mordant from a pervasive evil that threatens the land. Terisa is no champion. She wields neither magic nor power. And yet, much to her own surprise, when Geraden begs her to come back with him, she agrees.

[CyclopsBane]

I believe this subgenre is actually (and aptly) called "portal fantasy".

If you do a Google search for it (adult fantasy portal) you can find all sorts of lists. Harry Potter is a another good example. Lev Grossman's The Magicians is another, more adult one.

My favorite, and I'm not sure if this quite qualifies, is Piers Anthony's Xanth series. It takes place in a magical land shaped exactly like Florida, and there are portals that can take the wizards there to the real Florida (obviously not magical, unless you count Disney World ). So it's sort of a reverse portal fantasy. Fun to read though!