Favorite Concept Albums?

Another great concept album is Genesis-The Lamb Lies Down On Broadway. Metal or not, great prog rock, great concept. This is, of course, before Genesis went all soft and Adult Contemporary on everyone. Also is Yes's "Relayer" a concept album? Same With Helloween's Keeper Of The Seven Keys albums, are they concept albums?
 
Here's my picks:

The Afghan Whigs - Black Love
Pink Floyd - The Wall
November's Doom - The Knowing
Dredg - Leitmotif
Ulver - Themes from William Blake's Marriage of Heaven and Hell
Ephel Duath - The Painter's Palette

And a concept album is NOT a coherent story based album, it is an album with a conceptual theme that ties all the songs together. For example, while The Painter's Palette does not feature a story tying everything together, each song represents a different color for synaesthetes.
 
My favorites would have to be:
Emperor - Prometheus: The Discipline of Fire and Demise
Mayhem - A Grand Declaration of War (its a concept album)

(Its funny, as these are considered the worst albums by these artist...)
 
King Diamond - 'Abigail', 'Them'/'Conspiracy'
Dream Theater - Metropolis 2 - 'Scenes From a Memory'
Evergrey - 'In Search of Truth'
Soilwork - 'Predator's Portrait'
Iron Maiden - 'Seventh Son...'
Pink Floyd - 'The Wall'
 
I have to go with the popular vote here. 15 years after it's release, Queensryche's "Operation Mindcrime" is still a killer album.

Vanden Plas - Beyond Daylight is also a great work.

Bryant
 
I'm not sure if it was said already but Blind Guardian - "Nightfall in Middle Earth".
Also Jag Panzer - "Thane to the Throne" (always loved Macbeth)
 
Opeth - MAYH
Opeth - Still Life
EoS - Crimson
Therion - Secret of the Runes
Vehemence - God Was Created
Star One - Space Metal
Nightingale - I
Nightingale - Alive Again
Diabolical Masquerade - Death's Design

And if you wanna count 'em
motW - Bath and LYBM

That's all I can think of off the top of my head.
 
Blind Guradian- Nightfall in Middle Earth
Pink Floyd- The Wall
Yes- Tales of Topographic Oceans
Symphony X- Oddysey
And...

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