Your favorite 'concept' album

I'm not a concept album fan, however there are a few I've gone down the rabbit hole with. My personal fave, is '10,000 Years' by The Honeydogs. The backstory & lyrics are so vivid, and futuristic, it never fails to reveal something new to me. Even the bandleader said at times he's not sure what it's about.

Fascinating info & interview in the url. Check it out! 

Any others? 
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The two Jimmy Webb/Richard Harris LPs.  Ziggy Stardust.  Sgt. Pepper.
The Wall
Radio Kaos
The Final Cut

Ogden's Nut Gone Flake
The Magic Garden
The Shaming Of The True
Jeff Wayne's Musical Version Of The War Of The Worlds
The Who; "Quadrophenia" and  "Tommy"
The Kinks Arthur
The Who Tommy
Hall and Oates - War Babies
Spandau Ballet - Through the Barricades
“Stationary Traveller” - Camel
”Hope” - Klaatu
”Fear of a Blank Planet” - Porcupine Tree
”Fear of Music” - Talking Heads. 
Soap Opera good
I like Arthur (a TV special opera) better
Face To Face predates SF SorrowMy first concept was West Side Story OST 1961

Not a lotta love here for American Idiot
(We suspect who he is.)
One of the few besides Tommy to make it to the stage.
Speaking of, the IoW recording was an amazing journey.
The Kinks are the Village Green Preservation Society.

The young Ray was already deeply nostalgic, as were many of his mid/late 60s contemporaries. Blame the drugs.

I should also mention Windy by Astrud Gilberto. It's more of a (summery) mood album that also feels like a concept one.
Mannheim Steamroller Fresh Aire 7. Chip Davis does an excellent job of putting together pieces that all relate to or are based upon the number VII. Excellent demo disc as well for testing a system.

Smile by Brian Wilson and Van Dyke Parks.

Queensryche- "Operation: Mindcrime"
Certainly not my favourites but it might be interesting to some...

Fairport Convention 'Babbacombe Lee'

Jethro Tull 'Thick as a brick'

Hejira ~ Joni Mitchell
Thick as a Brick is a good one.
Rick Wakeman’s Journey to the Center of th Earth. In fact, I think I’ll put it on right now...  Or rather, after Morph the Cat by Donald Fagan.  Which, despite the name, isn’t a concept album. Just a good album. 
Alan Parson Project--you pick.
Rick Wakeman - Six Wives of Henry VIII
Red Headed Stranger, Pet Sounds, Sgt. Pepper's Lonely Hearts Club Band, Joe's Garage, Rust Never Sleeps, Welcome to My Nightmare, The Band, Hank Wilson's Back, The Delivery Man, Tarkus, Preservation Act 1 and Act 2, Stop Making Sense to list only a few I can think of immediately.

Then you have albums like Copeland: The Music of America that contains pieces that are all related and become a concept when they are put together and listened to in the album sequence.

I guess it depends on your definition of concept album.
Stones' Their Satanic Majesties Request = nostalgia for acid trips.
" Days of Future Passed" by the Moody Blues
" Days of Future Passed" by the Moody Blues

That is a very good one...
Pet Sounds - The Beach Boys 1965

Sgt. Pepper’s Lonely Hearts Club Band - The Beatles 1967

Tommy - The Who 1969

What’s Going On - Marvin Gaye 1971 *a work of art - a masterpiece with cultural, political and full of life consequential that reverberates to this very day*

Todd Rundgren - Something/Anything? 1972

Thick as a brick - Jethro Tull 1972

The Clones of Dr. Funkenstein - Parliament-Funkadelic 1976

Stevie Wonder
Frank Zappa

Pink Floyd Wish You Were Here

Moody BLues Days of Future Passed

King Crimson In the Court of the Crimson King
Bat out of Hell - Meatloaf
I don't think that King Crimson album is a concept album.
Ocean by Eloy.
The Alchemist by Home.
History of Melody Nelson by Serge Gainsbourg.
Also Joe's garage and Babbacombe Lee listed above are pretty awesome audiophile quality recordings.

Yoshimi Battles the Pink Robots
Amused to Death

Amused to death is a recording technology marvel. Nobody makes sound come way outside of the speakers location better than Roger.
However overall Zappa has better sound imaging throughout the entire spectrum. Dire Straits and Supertramp are not bad either :)
Operation:  mindcrime from Queensryche  an album everyone should have.
There's a Riot Goin' On - Sly and The Family Stone 1971

America Eats Its Young - Funkadelic 1972 

How did I forget these?

Please forgive me y'all for having flashbacks of riots.
2112 - RUSH
Tommy - The Who
Yoshimi Battles the Pink Robots - The Flaming Lips 
Days of Future Passed  - The Moody Blues
Radio Kaos - Roger Waters
The Wall - Pink Floyd
War Of The Worlds - The Moody Blues

A lot of good ones have been mentioned. I want to add Kilroy Was Here by Styx. 
Quadrophenia & The Lamb Lies Down on Broadway
As audite mentions tons of good stuff.

My own is Aftermath.  Can anyone figure out the concept?
Triumvirat - Sparticus, Rick Wakeman - Journey to the Center of the Earth, Genesis - The Lamb Lies Down on Broadway
Will skip the obvious one like 'Tubular bells' and post Tangerine Dream's


On somewhat lighter note

Brian Eno 'Apollo'
Thick As A Brick - Jethro Tull. It used to be Sergeant Pepper but I find the Tull album more interesting.  
David Bedford “The Rime of the Ancient Mariner”

Mike Oldfield “Ommadawn”

Camel “Snow Goose”
Coltrane's " A Love Supreme"
Gotta go with Sgt. Pepper and Pet Sounds.

Geniuses at work!

Another vote for Queensryche's Operation Mindcrime Album. If you're a fan of rock music of any kind, this album is a masterpiece.