Grimston Warren Pit

{{Short description|Protected area in Norfolk, England}}

{{Infobox SSSI

|image= Grimston Warren Pit 1.jpg

|image_caption =

|name= Grimston Warren Pit

|aos= Norfolk, England

|interest=Geological

|gridref={{gbmappingsmall|TF 673 222}}

|area= {{convert|6.6|ha|acre|abbr=off}}

|notifydate= 1996

|map=[http://magic.defra.gov.uk/MagicMap.aspx?startTopic=Designations&activelayer=sssiIndex&query=HYPERLINK%3D%272000172%27 Magic Map]

}}

Grimston Warren Pit is a {{convert| 6.6 |ha|acre|abbr=off |adj=on }} geological Site of Special Scientific Interest east of King's Lynn in Norfolk, England.{{cite web|url= https://designatedsites.naturalengland.org.uk/SiteDetail.aspx?SiteCode=S2000172&SiteName=&countyCode=29&responsiblePerson=&SeaArea=&IFCAArea= |title=Designated Sites View: Grimston Warren Pit | series= Sites of Special Scientific Interest|publisher=Natural England|access-date = 1 June 2018}}{{cite web|url= http://magic.defra.gov.uk/MagicMap.aspx?startTopic=Designations&activelayer=sssiIndex&query=HYPERLINK%3D%272000172%27|title=Map of Grimston Warren Pit|series= Sites of Special Scientific Interest|publisher=Natural England|access-date= 1 June 2018}} It is a Geological Conservation Review site.{{cite web|url=http://jncc.defra.gov.uk/default.aspx?page=4174&gcr=1233 |title= Grimston Warren (Berriasian, Valanginian, Hauterivian, Barremian) |series=Geological Conservation Review |publisher=Joint Nature Conservation Committee|access-date= 25 May 2018}}

This former quarry is described by Natural England as "a nationally important site for dating the constituent facies of the Lower Cretaceous in north Norfolk". It has yielded ammonites which date to the Hauterivian age around 130 million years ago.{{cite web|url= https://designatedsites.naturalengland.org.uk/PDFsForWeb/Citation/2000172.pdf |title=Grimston Warren Pit citation|series= Sites of Special Scientific Interest|publisher=Natural England|access-date= 1 June 2018}}

The site is private land with no public access.