{{short description|Island in north-east Hong Kong}} {{stack|{{Infobox islands | name = Kat O | local_name = 吉澳 | image_name = Kut O Pier part 7 in May 2026.jpg | image_caption = The pier of Kat O | map_image = Crooked Island - Hong Kong.svg | map_caption = Location of Kat O in Hong Kong | location = [[North District, Hong Kong|North District]] | area_km2 = 2.35 | length_km = <!-- or |length_m= --> | width_km = <!-- or |width_m= --> | coastline_km = <!-- or |coastline_m= --> | elevation_m = 122 | highest_mount = Kai Kung Leng <br>({{zh|t=雞公嶺|labels=no}}) | country = {{HKG}} | population = | population_as_of = }}{{Infobox Chinese |order= |showflag= |t=吉澳 |j=Gat<sup>1</sup> ou<sup>3</sup> |y=Gāt ou |h=Ket au |l=Crooked Island }} }} [[File:渔村 - panoramio.jpg|thumb|Village houses near the coast]] '''Kat O''' ({{zh|t=吉澳}}), also named '''Crooked Island''', is an [[island]] in northeast [[Hong Kong]].

==Administration== Administratively, Kat O is part of [[North District, Hong Kong|North District]]. It is a recognized village under the [[New Territories]] [[Small House Policy]].<ref>{{cite web |url=https://www.landsd.gov.hk/doc/en/small-house/rv0909.pdf |title=List of Recognized Villages under the New Territories Small House Policy |last= |first= |date=September 2009 |website= |publisher=[[Lands Department]] |access-date= |quote=}}</ref>

==Geography== [[File:Tin Hau Temple, Kat O in May 2026.jpg|thumb|[[Tin Hau temples in Hong Kong|Tin Hau Temple]] on Kat O]] [[File:Wong Kok Teng.jpg|thumb|Camp Cove ({{zh|t=白沙頭灣|labels=no}}) in the southern part of Kat O]] Kat O is located in the west of [[Mirs Bay]].<ref name="Nature Trail">Hong Kong Geopark: [http://www.geopark.gov.hk/en_s2b2i.htm Kat O Nature Trail]</ref> With an area of 2.35&nbsp;km²,<ref>Survey and Mapping Office, Lands Department: [http://www.landsd.gov.hk/mapping/en/publications/hk_geographic_data_sheet.pdf Hong Kong geographic data sheet]</ref> it is the largest island in North District, the second largest being [[Double Island, Hong Kong|Wong Wan Chau]] (Double Island).<ref name="Campbell">{{Cite web |url=http://ebook.lib.hku.hk/HKG/B35840158.pdf |title=K.W. Lai, S.D.G. Campbell & R. Shaw, ''Geology of the Northeastern New Territories'', p. 15, Civil Engineering Dept, Geotechnical Engineering Office, December 1996 |access-date=2011-07-12 |archive-date=2012-03-12 |archive-url=https://web.archive.org/web/20120312095428/http://ebook.lib.hku.hk/HKG/B35840158.pdf |url-status=dead }}</ref> Neighbouring islands include [[Ap Chau]], [[Ngo Mei Chau]] (Crescent Island), and [[Pak Sha Chau (North District)|Pak Sha Chau]] (Round Island). The village of Tung O ({{zh|t=東澳|labels=no}}) is located on its northwest coast.<ref name="Campbell"/> Its highest point is Kai Kung Leng ({{zh|t=雞公嶺|labels=no}}), which is 122 m above sea level.<ref name="Nature Trail"/>

O Pui Tong ({{zh|t=澳背塘|labels=no}}) is a bay surrounded by the crook-shaped Crooked Island and [[Yeung Chau, North District|Yeung Chau]].<ref>{{cite web |url=http://www.waterman.hku.hk/fisheries/public/fcz.aspx?code=OPT |title=O Pui Tong Fish Culture Zone |last= |first= |date= |website=Project WATERMAN|publisher=[[The University of Hong Kong]] |access-date= |quote=}}</ref> O Pui Tong, together with the northwestern waters of Kat O, are two of the 26 designated [[Agriculture and aquaculture in Hong Kong|marine fish culture zones]] in Hong Kong.<ref name="fisheries culture">{{cite web|url=https://www.afcd.gov.hk/english/fisheries/fish_aqu/fish_aqu_mpo/fish_aqu_mpo.html|title=Marine fish culture, pond fish culture and oyster culture |date=12 August 2019|access-date=16 December 2019|department=Fisheries Branch|publisher=Agriculture, Fisheries and Conservation Department}}</ref>

==History== Kat O was once a major fishing market in Hong Kong,<ref name='gradeiii'>[[Antiquities Advisory Board]]. Historic Building Appraisal. [https://www.aab.gov.hk/filemanager/aab/common/historicbuilding/en/974_Appraisal_En.pdf Tin Hau Temple, Sai O, Kat O]</ref> and long served as an important stopover for boats travelling between Hong Kong and the rest of China.<ref name=Rhoda>[https://hongkongfp.com/2020/09/06/hkfp-venture-kat-o-hong-kongs-forgotten-island-once-its-international-gateway/ HKFP Venture: Kat O, Hong Kong’s forgotten island – once its international gateway], HKFP, by Rhoda Kwan. 6 Sept 2020</ref>

During the [[Ming dynasty]], a decree required all inhabitants to leave the island. Then in the 1660s, soon after the end of the dynasty, it was re-settled by [[Hakka]] people.<ref name=Rhoda/> Other residents were [[Tanka people|Tanka]] fishermen.<ref name='gradeiii'/>

==Features== The [[Tin Hau temples in Hong Kong|Tin Hau Temple]] at Kat O is estimated to be built in 1763.<ref>{{Cite web |url=http://www.gohk.gov.hk/text/eng/welcome/north_spots.html |title=Welcome to 18 Districts - North District |access-date=2013-11-23 |archive-date=2013-12-03 |archive-url=https://web.archive.org/web/20131203082146/http://www.gohk.gov.hk/text/eng/welcome/north_spots.html |url-status=dead }}</ref> It is listed as a [[Heritage conservation in Hong Kong|Grade III]] historic building.<ref>[[Antiquities Advisory Board]]. [https://www.aab.gov.hk/filemanager/aab/en/content_29/AAB-SM-chi.pdf List of the 1,444 Historic Buildings with Assessment Results]</ref> Part of the temple building was used for the <!--spelling? Tat or Kat?-->Tat O School until the school was moved to a new location in 1957.<ref name='gradeiii'/> A [[Pak Kung Shrine]] is also located in the vicinity.<ref name='factfile'>{{Cite web|url=http://www.hktrampers.com/FactFile/CrookedIsland/|archive-url=https://web.archive.org/web/20160304085922/http://www.hktrampers.com/FactFile/CrookedIsland/|url-status=dead|archive-date=2016-03-04|title=Crooked Island|date=2016-03-04|access-date=2019-05-10}}</ref>

The island is home to three cannons. These are thought to have been made in the west, during the 19th century.<ref name='factfile'/>

==Conservation== Kat O has been part of the [[Plover Cove (Extension) Country Park]] since 1979.<ref>[http://www.afcd.gov.hk/english/country/cou_vis/cou_vis_cou/cou_vis_cou_pc/cou_vis_cou_pc.html Agriculture, Fisheries and Conservation Department: Plover Cove Country Park] {{webarchive|url=https://web.archive.org/web/20130929084031/http://www.afcd.gov.hk/english/country/cou_vis/cou_vis_cou/cou_vis_cou_pc/cou_vis_cou_pc.html |date=2013-09-29 }}</ref>

The Kat O Nature Trail is 1 km long, stretching from the Kat O Ferry Pier to Ko Tei Teng ({{zh|t=高地頂|labels=no}}).<ref name="Nature Trail"/>

The Kat O Geoheritage Centre (at No. 142 Kat O Main Street) was opened in 2010<ref>[[Time Out (magazine)|''Time Out'' Hong Kong]]: [http://www.timeout.com.hk/around-town/features/66009/secret-hong-kong-islands.html "Secret Hong Kong islands"] {{Webarchive|url=https://web.archive.org/web/20140905010706/http://www.timeout.com.hk/around-town/features/66009/secret-hong-kong-islands.html |date=2014-09-05 }}, 29 Apr 2014</ref> by Kat O villagers, volunteer groups and the government to raise public awareness of geo-conservation, as part of the [[Hong Kong UNESCO Global Geopark|Hong Kong Geopark]].<ref>Hong Kong Geopark: [http://www.geopark.gov.hk/en_s2f3.htm Kat O Geoheritage Centre]</ref>

==See also== {{portal|Islands}} * [[Crooked Harbour]] * [[Double Haven]] * [[Pat Sin Leng Country Park]]

==References== {{Reflist}}

==Further reading== * {{cite journal|last=Choi|first=C.C.|author-link1=|year=1990|title=Studies on Hong Kong Jiao Festivals|journal=Journal of the [[Royal Asiatic Society Hong Kong Branch]]|volume=30|pages=26-43|publisher=|url=https://hkjo.lib.hku.hk/archive/files/6961e3917fbbd2702e62721f4604d7d8.pdf|issn=1991-7295|accessdate=}}{{Dead link|date=August 2025 |bot=InternetArchiveBot |fix-attempted=yes }}

==External links== {{commons category|Crooked Island, Hong Kong}} * [https://www.had.gov.hk/rre/images/village_map1922/N/n-stk-37.pdf Delineation of area of existing village Kat O (Sha Tau Kok) for election of resident representative (2019 to 2022)] * [http://www.kut-o.com/ Kut-O Chinese Association (Kent area) Website] * Pictures of Kat O: [http://www.kut-o.com/archive.htm], [http://thaiworldview.com/hongkong/outerisland/kat%20o.htm] * Hong Kong Geopark: [http://www.geopark.gov.hk/en_s3fk.htm "Lee Yuk Ying Introduces the Cultural History of Kat O to Visitors"]. * [http://www.hktrampers.com/FactFile/CrookedIsland/ Webpage about Kat O] {{Webarchive|url=https://web.archive.org/web/20160304085922/http://www.hktrampers.com/FactFile/CrookedIsland/ |date=2016-03-04 }} * [[Antiquities Advisory Board]]. [https://www.aab.gov.hk/filemanager/aab/common/historicbuilding/photo/974_Photo.pdf Pictures of Tin Hau Temple, Sai O, Kat O] * [https://edition.cnn.com/travel/article/ap-chau-kat-o-hong-kong-cmd/index.html How to visit two of Hong Kong's most remote islands in one day] CNN.com {{North District, Hong Kong}} {{Islands of Hong Kong}}

{{Coord|22|32|28|N|114|17|43.9|E|display=title|type:isle}}

[[Category:Islands of Hong Kong]] [[Category:North District, Hong Kong]] [[Category:Hong Kong UNESCO Global Geopark]] [[Category:Populated places in Hong Kong]]