600-699
- 600: TLC Observatory, Bologna
- 601: Engelhardt Observatory, Dresden
- 602: Urania Observatory, Vienna
- 603: Bothkamp, near Kiel, Germany (Sternwarte Bothkamp, Bothkamp Observatory)
- 604: Archenhold Sternwarte, Berlin-Treptow
- 605: Marl
- 606: Norderstedt
- 607: Hagen Observatory, Ronkhausen
- 608: Haleakala-AMOS, Hawaii, USA
- 609: Osservatorio Polino
- 610: Pianoro
- 611: Starkenburg Sternwarte, Heppenheim (Starkenburg Observatory)
- 612: Lenkerbeck
- 613: Heisingen
- 614: Soisy-sur-Seine
- 615: St. Véran
- 616: Brno
- 617: Arbonne-la-Forêt
- 618: Martigues
- 619: Sabadell
- 620: Observatorio Astronómico de Mallorca
- 621: Bergisch Gladbach Observatory
- 622: Oberwichtrach
- 623: Liège
- 624: Dertingen
- 625: Kihei-AMOS Remote Maui Experimental Site, Hawaii, USA
- 626: Geel
- 627: Blauvac
- 628: Mülheim-Ruhr
- 629: Szeged Observatory, Szeged, Hungary JATE Observatory
- 630: Osenbach
- 631: Hamburg-Georgswerder
- 632: San Polo A Mosciano
- 633: Romito
- 634: Crolles
- 635: Pergignan
- 636: Essen Observatory aka Walter Hohmann Observatory, Germany
- 637: Hamburg-Himmelsmoor
- 638: Detmold
- 639: Dresden
- 640: Senftenberger Sternwarte
- 641: Overberg
- 642: Oak Bay, Victoria
- 643: OCA-Anza Observatory, Anza, California, USA
- 644: Palomar Mountain/NEAT, California, USA (Palomar Observatory)
- 645: Apache Point-Sloan Digital Sky Survey, Sunspot, New Mexico, USA (Apache Point Observatory)
- 646: Santana Observatory, Rancho Cucamonga, California, USA
- 647: Stone Finder Observatory, Calgary, Canada
- 648: Winer Observatory, Sonoita, Arizona, USA
- 649: Powell Observatory, Louisburg, Kansas, USA
- 650: Temecula, California, USA
- 651: Grasslands Observatory, Tucson, Arizona, USA
- 652: Rock Finder Observatory, Calgary, Canada
- 653: Torus Observatory, Buckley
- 654: Table Mountain Observatory, Wrightwood-PHMC, California, USA
- 655: Sooke
- 656: Victoria
- 657: Climenhaga Observatory, Victoria, British Columbia, Canada
- 658: National Research Council of Canada (Dominion Astrophysical Observatory, Saanich, British Columbia, Canada)
- 659: Heron Cove Observatory, Orcas', Washington, USA
- 660: Leuschner Observatory, Berkeley, California, USA
- 661: Rothney Astrophysical Observatory, Priddis, Alberta, Canada
- 662: Lick Observatory, Mount Hamilton, California, USA
- 663: Red Mountain Observatory, Ivins, Utah, USA
- 664: Manastash Ridge Observatory, Ellensburg, Washington, USA
- 665: Wallis Observatory
- 666: Moorpark College Observatory, Ventura County, California, USA
- 667: Wanapum Dam
- 668: San Emigdio Peak
- 669: Ojai
- 670: Camarillo
- 671: Stony Ridge
- 672: Mount Wilson, California, USA
- 673: Table Mountain Observatory, Wrightwood, California, USA
- 674: Ford Observatory, Wrightwood, California, USA
- 675: Palomar Mountain, California, USA (Palomar Observatory)
- 676: San Clemente, California, USA
- 677: Lake Arrowhead, California, USA
- 678: Fountain Hills, Fountain Hills, Arizona, USA (Fountain Hills Observatory)
- 679: San Pedro Martir, Baja California, Mexico (National Astronomical Observatory (Mexico))
- 680: Los Angeles, California, USA
- 681: Calgary
- 682: Kanab
- 683: Goodricke-Pigott Observatory, Tucson, Arizona, USA
- 684: Prescott, Arizona, USA (Prescott Observatory)
- 685: Williams, Arizona, USA
- 686: U. of Minn. Infrared Obs., Mt. Lemmon, Arizona, USA (UMN Mount Lemmon Observing Facility)
- 687: Northern Arizona University, Flagstaff, Arizona, USA
- 688: Lowell Observatory, Anderson Mesa Station, Arizona, USA
- 689: U.S. Naval Observatory, Flagstaff, Arizona, USA (NOFS)
- 690: Lowell Observatory, Flagstaff, Arizona, USA
- 691: Steward Observatory, Kitt Peak-Spacewatch, Arizona, USA
- 692: Steward Observatory, Tucson, Arizona, USA
- 693: Catalina Station, Tucson, Arizona, USA
- 694: Tumamoc Hill, Tucson, Arizona, USA (Steward Observatory)
- 695: Kitt Peak National Observatory, Arizona, USA
- 696: Whipple Observatory, Mt. Hopkins, Arizona, USA (Fred Lawrence Whipple Observatory)
- 697: Kitt Peak, McGraw-Hill, Arizona, USA (MDM Observatory)
- 698: Mt. Bigelow, Arizona, USA
- 699: Lowell Observatory-LONEOS, Anderson Mesa Station, Arizona, USA
Read more about this topic: List Of Observatory Codes