Sites of Special Scientific Interest (SSSIs)
Safleoedd o Ddiddordeb Gwyddonol Arbennig (SoDdGA)

  • English
  • wel
  • All

This spatial dataset contains the digital boundaries of Sites of Special Scientific Interest (SSSIs) in Wales. SSSIs cover a wide range of habitats from small fens, bogs and riverside meadows to sand-dunes, woodlands and vast tracts of uplands. Most are in private ownership, although some are owned and managed by local wildlife trusts, or other voluntary conservation bodies.


Notification of an SSSI under the Wildlife and Countryside Act 1981 has since been amended by the Countryside and Rights of Way Act 2001, which brought about numerous changes in the way SSSI are notified managed and protected.


In order to ensure consistent, favourable long-term management of these sites, Natural Resources Wales (NRW) with landowners have prepared management plans for all SSSI in Wales. Local planning authorities are required to consult NRW before allowing any development to proceed that may affect an SSSI. Water, gas and electricity companies must also do the same.


SSSIs have been designated, from 1949 to the present day, and are on-going. The data has been held digitally since the mid-1990s. This data has been checked by relevant NRW staff. Please refer to the designation map as the legal definitive boundary. For large SSSIs that were captured digitally and have been printed on a smaller scale map than OS MasterMap, please refer to the OS MasterMap edition at time of capture to view the definitive boundary.

Mae'r set ddata ofodol hon yn cynnwys ffiniau Safleoedd o Ddiddordeb Gwyddonol Arbennig (SoDdGA) yng Nghymru. Mae SoDdGA yn cwmpasu amrywiaeth eang o gynefinoedd megis ffeniau bach, corsydd, dolydd glan afon, twyni tywod, coetiroedd ac ardaloedd helaeth o ucheldir. Mae'r rhan fwyaf mewn perchnogaeth breifat, er bod rhai yn eiddo i ac yn cael eu rheoli gan ymddiriedolaethau bywyd gwyllt lleol neu gyrff cadwraeth gwirfoddol eraill. Mae dynodiad SoDdGA dan Ddeddf Bywyd Gwyllt a Chefn Gwlad 1981 wedi ei ddiwygio gan Ddeddf Cefn Gwlad a Hawliau Tramwy 2001, a gyflwynodd newidiadau niferus i'r ffordd y mae SoDdGA yn cael eu dynodi, eu rheoli a'u gwarchod. Er mwyn sicrhau bod rheolaeth hirdymor yr ardaloedd hyn yn gyson a ffafriol mae Cyfaeth Naturiol Cymru, ar y cyd thirfeddianwyr, wedi paratoi cynlluniau rheoli ar gyfer pob SoDdGA yng Nghymru. Mae'n ofynnol i awdurdodau cynllunio lleol ymgynghori â CNC cyn caniatáu i unrhyw ddatblygiad fynd rhagddo a allai effeithio ar SoDdGA. Mae'n rhaid i gwmnau dŵr, nwy a thrydan wneud hynny hefyd. Mae SoDdGA wedi cael eu dynodi dros nifer o flynyddoedd, o 1949 hyd heddiw, ac maent yn parhau.


Datganiad priodoli


Yn cynnwys gwybodaeth Cyfoeth Naturiol Cymru © Cyfoeth Naturiol Cymru a Hawl Cronfa Ddata. Cedwir pob hawl. Yn cynnwys data Arolwg Ordnans. Rhif Trwydded Arolwg Ordnans AC0000849444. Hawlfraint y Goron a Hawl Cronfa Ddata.

Identification

Dynodydd
Identifier
NRW_DS98776
Teitl Amgen
Alternative Title
  • Sites of Special Scientific Interest (SSSI).lyr
  • Sites (SSSI)
Laith Metadata
Metadata Language
English
Lineage

All SSSIs designated before GIS technology have been converted into digital data from paper maps of various scales. In 2008 the whole dataset was updated to OS MasterMap (mostly to CCW 2006 OS update). This update referred to the original designation maps and all notational descriptions on these maps e.g. “Only the water under the bridges included in the site” OR “SSSI boundary follows, in part the lines of the Mean High and Low Water Marks; both are liable to change.” All new or re-notified sites will be put to the latest release by NRW of OS MasterMap and this information is recorded in the attribute data under the Last_Edited column. As OSMM is updated by the Ordnance Survey it is important to check where boundaries may subsequently have moved.
Additional Information

Please refer to Countryside Acts 1949,1981 and 2001, for reasons for capture of original designation. NRW has also created a subset of this dataset showing only those where relate to the marine environment. These are available on the Welsh Government marine planning portal.
Dyddiad cyfeirnod y set ddata (Cyhoeddiad)
Dataset Reference Date (Publication)
2026-08-12

Temporal Extent

Begin date
1992-01-01
 
Categori pwnc
Topic category
  • Biota
    Biota
  • Environment
    Environment
  • Imagery base maps earth cover
    Imagery base maps earth cover
  • Geoscientific information
    Geoscientific information
Perchennog
Owner
  Natural Resources Wales (NRW) -
Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales
http://naturalresources.wales/?lang=en
Cychwynnwr
Originator
  Natural Resources Wales (NRW) -
Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales
http://naturalresources.wales/?lang=en
 

Extent

Extent

Hyd
Geographic Extent
Wales (WLS)
N
W
E
S
Map representing the geographic extent of the dataset


 

Vertical Extent

Medin Extent Keyword
inapplicable
 
 

Distribution

Dosbarthiad
Distribution

Fformat - Math a Disgrifiad
Format Type and Description
  • Geographic Information System ( )

    Specification

    ESRI Feature Class

Lleolwr Adnoddau
Resource Locator
Download Data and Web Service ( WWW:LINK-1.0-http--link )
Lleolwr Adnoddau
Resource Locator
Web Mapping Service ( OGC:WMS )
 

Quality

Ansawdd Data
Data quality

Cwmpas Ansawdd
Quality Scope
Dataset
Dataset
Cydymffurfiad
Conformity
Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards interoperability of spatial data sets and services
Explanation

This dataset has not been assessed for conformance to the referenced INSPIRE regulation.
Degree
false
Lineage

All SSSIs designated before GIS technology have been converted into digital data from paper maps of various scales. In 2008 the whole dataset was updated to OS MasterMap (mostly to CCW 2006 OS update). This update referred to the original designation maps and all notational descriptions on these maps e.g. “Only the water under the bridges included in the site” OR “SSSI boundary follows, in part the lines of the Mean High and Low Water Marks; both are liable to change.” All new or re-notified sites will be put to the latest release by NRW of OS MasterMap and this information is recorded in the attribute data under the Last_Edited column. As OSMM is updated by the Ordnance Survey it is important to check where boundaries may subsequently have moved.
 

Keywords

Allweddair
Keywords

GEMET - INSPIRE themes, version 1.0
Math
Type
Theme
Theme

Dyfyniad
Citation

Dyddiad (Cyhoeddiad)
Date (Publication)
2008-06-01
Code
geonetwork.thesaurus.external.theme.httpinspireeceuropaeutheme-theme

Allweddair
Keywords

NRW Thesaurus
  • Site of Special Scientific Interest (SSSI)
  • habitats (see also specific types of habitats)
  • geographical information systems (GIS)
  • conservation (see also conservation of specific subjects)
Math
Type
Theme
Theme

Dyfyniad
Citation

Dyddiad (Cyhoeddiad)
Date (Publication)
2026-07-24
Code
geonetwork.thesaurus.local.theme.converted_nrw-keywords

Allweddair
Keywords

SeaDataNet Parameter Discovery Vocabulary
Math
Type
Theme
Theme

Dyfyniad
Citation

Dyddiad (Cyhoeddiad)
Date (Publication)
2024-06-19
Code
geonetwork.thesaurus.external.theme.rdf+xml

Allweddair
Keywords

NRW SMNR Keywords
  • Cultural Services (SMNR)
  • Ecosystem Services (SMNR)
  • Marine (SMNR)
  • Mountains, Moorland and Heaths (SMNR)
  • Soil and Land (SMNR)
  • Ecosystem (SMNR)
  • Freshwater and Wetlands (SMNR)
  • Sustainable Management of Natural Resources (SMNR)
  • Natural Resources (Incl. Features and Processes) (SMNR)
  • Regulating Services (SMNR)
  • Woodlands (SMNR)
  • Sea and Coast (SMNR)
  • Management Areas (SMNR)
  • Physical Geography (Physiography) (SMNR)
  • Provisioning Services (SMNR)
  • Coastal Margins (SMNR)
  • Semi-natural Grasslands (SMNR)
  • Animals, Plants and Other Organisms (SMNR)
Math
Type
Theme
Theme

Dyfyniad
Citation

Dyddiad (Cyhoeddiad)
Date (Publication)
2024-06-26
Code
geonetwork.thesaurus.local.theme.converted_nrw-smnr-keywords
 

Spatial Reference System

Code
British National Grid (EPSG::27700)
 

Content

Gwybodaeth Cynnwys
Content Information

Proffil CNC
NRW Profile

Elfennau CNC
Custom Elements

 

Constraints

Constraints

Limitations on Public Access and Use

Math o Gyfyngiad
Restriction type
Other restrictions
Other restrictions
 

Access Constraints Directive

Limitations
no limitations
 

Access Constraints Text

Other constraints

There are no access restrictions on this data. NRW may release, publish or disseminate it freely.
 

Use Constraints

Cyfyngiadau Defnyddio
Use constraints type
Other restrictions
Other restrictions
Other constraints

© CNC/NRW All rights Reserved. Contains Ordnance Survey Data. Ordnance Survey Licence number AC0000849444. Crown Copyright and Database Right Data may be re-used under the terms of the Open Government Licence providing it is done so, acknowledging both the source and copyright of the owners. It is the recipient's responsibility to ensure the data is fit for the intended purpose.
 

Attribution Statement

Other constraints

Contains Natural Resources Wales information © Natural Resources Wales and Database Right. All rights Reserved. Contains Ordnance Survey Data. Ordnance Survey Licence number AC0000849444. Crown Copyright and Database Right.
 

Licence

Other constraints
Open Government Licence
 
 
 

Metadata

Metadata

Dynodydd Ffeil
File Identifier
4f4c4942-4343-5764-6473-3938373736 XML
Laith Metadata
Metadata Language
English
Math o adnodd
Resource type
Dataset
Dataset
Dyddiad Metadata
Metadata Date
2026-08-14T10:45:14.97Z
Enw Safonol Metadata
Metadata Standard Name
NRW
Fersiwn Metadata
Metadata Standard Version

1.0

Pwynt Cyswllt
pointOfContact
  Natural Resources Wales (NRW) -
Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales
http://naturalresources.wales/?lang=en
 
 

Publishing Body

Access the portal