Which nations are covered?

England, Wales and Scotland. Northern Ireland is excluded because its only ancient woodland inventory is a proprietary Woodland Trust product that cannot be released under the Open Government Licence. Including it would mean either breaching that licence or serving inconsistent coverage, so we leave it out and say so.

Is this a statutory designation?

The Ancient Woodland Inventory is a non-statutory dataset maintained by the national nature bodies. The woodland it records is nonetheless a material consideration with strong protection through national planning policy, the NPPF in England and the equivalent policy in Wales and Scotland. Some ancient woodlands are also designated as SSSIs, but inclusion in the inventory is not in itself a statutory designation.

How current is the data?

The data is snapshot-versioned and refreshed when a custodian republishes its inventory. The Welsh inventory is the 2021 revision. Because the national inventories change slowly, expect updates on roughly an annual cadence rather than continuously.

How is it licensed and delivered?

It is delivered read-only over REST at /v1/conservation, queried by point, radius, bounding box or polygon, or by stable id. The licence is the Open Government Licence v3.0 throughout. The commercial model is an annual licence rather than pay-per-call, and the /types vocabulary endpoint is free so you can evaluate coverage before buying.

What is the difference between ancient semi-natural woodland and plantation on ancient woodland sites?

Ancient semi-natural woodland (ASNW) retains native, naturally regenerated tree cover. Plantation on ancient woodland sites (PAWS) has been replanted, often with conifers, but the ancient soils and ground features remain, which is why it keeps its protected status. This harmonised classification sits in the premium value-domain tier.

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Ancient Woodland

Ancient woodland polygons for England, Wales and Scotland, reconciled from the national inventories of Natural England, Natural Resources Wales and NatureScot into one schema.

130,698

Polygons

3 nations

Coverage

EPSG:4326

Geometry

OGL v3.0

Licence

Overview

About this dataset

Ancient woodland is land that has been continuously wooded since around 1600 in England and Wales, and around 1750 in Scotland, the earliest dates from which reliable maps survive. It is treated as an irreplaceable habitat and given strong protection in national planning policy, so its presence on or near a site is a hard constraint for anyone buying land, lending against it, or taking a scheme through planning.

This product reconciles the three national Ancient Woodland Inventories into one schema: Natural England (53,638 polygons), the Natural Resources Wales Ancient Woodland Inventory 2021 (48,549) and NatureScot (28,511), roughly 130,000 polygons in total. Northern Ireland is deliberately excluded. The only ancient woodland inventory for Northern Ireland is a proprietary Woodland Trust product that cannot enter an Open Government Licence dataset, and we will not pass off partial or non-OGL coverage as complete.

Every polygon carries valid EPSG:4326 (WGS84) geometry, reprojected server-side from British National Grid, and a stable identifier of the form design.conservation.{nation}.ancient_woodland.{reference}. Query the data by point, radius, bounding box or polygon, or fetch one designation by id, over the REST endpoint at /v1/conservation. Each record returns its source custodian and a per-custodian attribution string, with the Open Government Licence v3.0 applied throughout.

Dates are served honestly. A date_precision flag records whether a value is exact to the day, month or year, so a year-only source date is never presented as a precise calendar date. The harmonised value-domain vocabulary, which separates ancient semi-natural woodland from plantation on ancient woodland sites, is the premium tier, and the public /types endpoint is free for evaluation.

What's included

Everything in the box

Three inventories, one schema

Natural England, Natural Resources Wales and NatureScot reconciled into a single record shape, with one stable id per polygon.

Point, radius or polygon query

Query by point, radius, bounding box or polygon, or fetch one designation by id, over REST at /v1/conservation.

EPSG:4326 geometry

Every polygon carries valid WGS84 geometry, reprojected server-side from British National Grid (EPSG:27700).

Clean OGL provenance

Open Government Licence v3.0 throughout, with per-custodian attribution on every record. Non-OGL sources are excluded by design, which is why Northern Ireland is not included.

Honest designation dates

A date_precision flag records whether a date is exact to the day, month or year, so a year-only source value is never served as a false calendar date.

Ancient woodland classification

A harmonised value-domain vocabulary distinguishes ancient semi-natural woodland from plantation on ancient woodland sites, and Welsh names are returned where the source provides them. This vocabulary is the premium tier.

Data fields

What each record carries

schema14 fields

reference: string// Identifier of the polygon within its originating national inventory.

nation: enum// Source nation: ENG, WAL or SCO.

source: string// The custodian and register the record came from.

name: string// Woodland name where the source supplies one. Many inventory polygons are unnamed.

name_cy: string// Welsh-language name where supplied by Natural Resources Wales.

designation_type: enum// Always ancient_woodland for this product.

category: string// The inventory's own classification of the woodland, as published by the custodian.

zone_subtype: enum// Harmonised value-domain subtype (premium tier): ancient_semi_natural or plantation_on_ancient_site.

area_hectares: float// Polygon area in hectares.

local_authority: string// Administrative area the polygon falls within.

designated_date: date// Date the polygon was recorded in or last revised by the inventory, subject to date_precision.

date_precision: enum// Honesty flag for designated_date: day, month, year or none.

centroid: object// Representative point of the polygon as lat and lng in EPSG:4326.

attribution: string// Per-custodian attribution string returned with every record.

Sample response

Straight from the API

response.jsonapplication/json

{
  "id": "design.conservation.WAL.ancient_woodland.48217",
  "reference": "48217",
  "nation": "WAL",
  "source": "Natural Resources Wales Ancient Woodland Inventory 2021",
  "name": "Coed y Bedw",
  "name_cy": "Coed y Bedw",
  "designation_type": "ancient_woodland",
  "category": "Ancient Semi-Natural Woodland",
  "zone_subtype": "ancient_semi_natural",
  "area_hectares": 12.43,
  "local_authority": "Cardiff",
  "designated_date": "2021-01-01",
  "date_precision": "year",
  "centroid": {
    "lat": 51.546,
    "lng": -3.281
  },
  "source_url": "https://datamap.gov.wales/maps/ancient-woodland-inventory-2021",
  "licence": "Open Government Licence v3.0",
  "attribution": "Contains Natural Resources Wales information © Natural Resources Wales and database right. Licensed under the Open Government Licence v3.0."
}

Use cases

What people build with it

Site due diligence

Screen a parcel for ancient woodland before acquisition or before submitting a planning application, since its loss is a strong constraint in national planning policy.

Developers

Planning constraint checks

Return every ancient woodland polygon intersecting a red-line boundary, with attribution, to support constraint reports and committee papers.

Planners

Mortgage and valuation risk

Flag whether a security property sits on or beside ancient woodland that limits future extension or development potential.

Surveyors

ESG and biodiversity screening

Screen portfolios and land holdings for irreplaceable habitat as part of nature-related risk and ESG reporting.

Investors

Constraint layer for proptech

Embed ancient woodland as a constraint layer in a site-sourcing or environmental search product through a single API.

PropTech