Klingon planets

"I thought I could trim two or three days off our journey by cutting across the most insignificant corner of Klingon space. I learned very quickly there's no thing as an insignificant corner of Klingon space. We were lucky to escape with our lives, though we did pay a price".
 * - Skalaar, 2153

The following is a list of mentioned planets and star systems in the Klingon Empire. All planets listed are or were inhabited at some point of time.

Planets

 * Archanis IV (Archanis sector, ceded to the Federation in the 23rd century, reconquered in 2373)
 * Boreth
 * Ganalda IV (conquered by the Federation in 2373)
 * H'atoria
 * Khitomer (Khitomer system, colony destroyed by Romulan forces in 2346, within Romulan territory as of 2369)
 * Krios Prime
 * Maranga IV (Maranga system)
 * Morska
 * Narendra III (Narendra system, attacked by Romulan forces in 2344)
 * N'Vak colony (colony destroyed by Klingon forces in 2154)
 * Organia (only briefly occupied in 2267)
 * Praxis (Klingon system, destroyed in 2293)
 * Qo'noS (Klingon system)
 * Qu'Vat colony
 * Raatooras
 * Rura Penthe (Beta Penthe system)
 * Sherman's Planet (shared possession in 2267, granted to the Federation as of 2269)
 * Ty'Gokor

Uncertain

 * Donatu V
 * Forcas III
 * Hitora colony
 * Korvat colony
 * Neural (claimed by the Empire in 2267)
 * Elas (Tellun system, claimed by the Empire in 2268)
 * Troyius (Tellun system, claimed by the Empire in 2268)
 * Tessic's colony
 * Xarantine homeworld

Stars and star systems

 * Beta Lankal
 * Beta Thoridar
 * Gamma Eridon
 * Mempa system
 * Pheben system

Other stellar phenomena

 * Azure Nebula (on the border to Federation space)
 * Baber Nebula
 * Barnes Nebula
 * Betreka Nebula (uncertain, may not really border the Klingon Empire)
 * Gullory Nebula
 * Hodges Nebula
 * Klach D'Kel Brakt (also called "Briar Patch", in Federation space as of 2375)
 * Vodrey Nebula (on the border to Federation space)