{
	"geographicCRS": {
		"EPSG:4277": {
			"code": "EPSG:4277",
			"name": "OSGB36",
			"type": "geographic",
			"datum": {
				"name": "Ordnance Survey of Great Britain 1936",
				"ellipsoid": "Airy 1830",
				"type": "geodetic"
			},
			"areaOfUse": {
				"description": "United Kingdom (UK) - Great Britain - England, Scotland, Wales - onshore",
				"bbox": {
					"north": 60.9,
					"south": 49.8,
					"east": 1.8,
					"west": -8.7
				},
				"regions": ["England", "Scotland", "Wales"]
			},
			"accuracy": {
				"horizontal": "~5m relative to ETRS89",
				"note": "Historic datum with local distortions"
			},
			"remarks": "Traditional datum for Great Britain. Use ETRS89 for new high-accuracy work. OSTN15 transformation required for accurate conversion to ETRS89.",
			"useCases": [
				"Legacy mapping data",
				"Ordnance Survey historic maps",
				"British National Grid coordinates"
			],
			"deprecated": false
		},
		"EPSG:4258": {
			"code": "EPSG:4258",
			"name": "ETRS89",
			"type": "geographic",
			"datum": {
				"name": "European Terrestrial Reference System 1989",
				"ellipsoid": "GRS 1980",
				"type": "geodetic"
			},
			"areaOfUse": {
				"description": "Europe - onshore and offshore",
				"bbox": {
					"north": 84.73,
					"south": 32.88,
					"east": 40.18,
					"west": -16.1
				}
			},
			"accuracy": {
				"horizontal": "1-2cm relative to ITRF",
				"note": "European reference frame coincident with ITRF at epoch 1989.0"
			},
			"remarks": "Recommended datum for new surveys in the UK and Europe. Practically identical to WGS84 for most applications.",
			"useCases": [
				"Modern surveying",
				"GNSS positioning",
				"European data exchange",
				"INSPIRE compliance"
			],
			"deprecated": false
		}
	},
	"projectedCRS": {
		"EPSG:27700": {
			"code": "EPSG:27700",
			"name": "OSGB36 / British National Grid",
			"type": "projected",
			"baseCRS": "EPSG:4277",
			"projection": {
				"name": "Transverse Mercator",
				"method": "Transverse Mercator",
				"parameters": {
					"latitudeOfOrigin": 49,
					"centralMeridian": -2,
					"scaleFactor": 0.9996012717,
					"falseEasting": 400000,
					"falseNorthing": -100000
				}
			},
			"areaOfUse": {
				"description": "United Kingdom (UK) - Great Britain - England, Scotland, Wales - onshore",
				"bbox": {
					"north": 60.9,
					"south": 49.8,
					"east": 1.8,
					"west": -8.7
				},
				"regions": ["England", "Scotland", "Wales"]
			},
			"accuracy": {
				"horizontal": "Survey-grade within Great Britain",
				"note": "National grid for Great Britain"
			},
			"remarks": "The national projected CRS for Great Britain. Used by Ordnance Survey for all mapping. Grid references use 100km squares (e.g., TQ 123 456).",
			"useCases": [
				"Ordnance Survey mapping",
				"Land surveying",
				"Planning and development",
				"Emergency services"
			],
			"deprecated": false
		},
		"EPSG:7405": {
			"code": "EPSG:7405",
			"name": "OSGB36 / British National Grid + ODN height",
			"type": "compound",
			"baseCRS": "EPSG:27700",
			"areaOfUse": {
				"description": "United Kingdom (UK) - Great Britain - England, Scotland, Wales - onshore",
				"regions": ["England", "Scotland", "Wales"]
			},
			"remarks": "Compound CRS combining BNG horizontal with Ordnance Datum Newlyn (ODN) heights.",
			"useCases": ["3D surveying", "Height referencing", "Engineering projects"],
			"deprecated": false
		},
		"EPSG:29902": {
			"code": "EPSG:29902",
			"name": "TM65 / Irish Grid",
			"type": "projected",
			"baseCRS": "EPSG:4299",
			"projection": {
				"name": "Transverse Mercator",
				"method": "Transverse Mercator",
				"parameters": {
					"latitudeOfOrigin": 53.5,
					"centralMeridian": -8,
					"scaleFactor": 1.000035,
					"falseEasting": 200000,
					"falseNorthing": 250000
				}
			},
			"areaOfUse": {
				"description": "Ireland - onshore",
				"regions": ["Northern Ireland", "Republic of Ireland"]
			},
			"remarks": "Historic Irish Grid. Superseded by Irish Transverse Mercator (ITM) for new work.",
			"useCases": ["Legacy Irish mapping", "Northern Ireland historic data"],
			"deprecated": true
		},
		"EPSG:2157": {
			"code": "EPSG:2157",
			"name": "IRENET95 / Irish Transverse Mercator",
			"type": "projected",
			"baseCRS": "EPSG:4173",
			"projection": {
				"name": "Transverse Mercator",
				"method": "Transverse Mercator",
				"parameters": {
					"latitudeOfOrigin": 53.5,
					"centralMeridian": -8,
					"scaleFactor": 0.99982,
					"falseEasting": 600000,
					"falseNorthing": 750000
				}
			},
			"areaOfUse": {
				"description": "Ireland - onshore",
				"regions": ["Northern Ireland", "Republic of Ireland"]
			},
			"remarks": "Modern Irish projection based on ETRS89. Recommended for all new work in Ireland including Northern Ireland.",
			"useCases": ["Modern Irish surveying", "Cross-border projects", "GNSS surveys"],
			"deprecated": false
		}
	},
	"zoneMapping": {
		"England": { "zone": "BNG", "code": "EPSG:27700", "name": "OSGB36 / British National Grid" },
		"Scotland": { "zone": "BNG", "code": "EPSG:27700", "name": "OSGB36 / British National Grid" },
		"Wales": { "zone": "BNG", "code": "EPSG:27700", "name": "OSGB36 / British National Grid" },
		"Northern Ireland": {
			"zone": "ITM",
			"code": "EPSG:2157",
			"name": "IRENET95 / Irish Transverse Mercator",
			"notes": "Irish Transverse Mercator"
		},
		"Greater London": {
			"zone": "BNG",
			"code": "EPSG:27700",
			"name": "OSGB36 / British National Grid"
		},
		"South East": { "zone": "BNG", "code": "EPSG:27700", "name": "OSGB36 / British National Grid" },
		"South West": { "zone": "BNG", "code": "EPSG:27700", "name": "OSGB36 / British National Grid" },
		"East of England": {
			"zone": "BNG",
			"code": "EPSG:27700",
			"name": "OSGB36 / British National Grid"
		},
		"East Midlands": {
			"zone": "BNG",
			"code": "EPSG:27700",
			"name": "OSGB36 / British National Grid"
		},
		"West Midlands": {
			"zone": "BNG",
			"code": "EPSG:27700",
			"name": "OSGB36 / British National Grid"
		},
		"Yorkshire and the Humber": {
			"zone": "BNG",
			"code": "EPSG:27700",
			"name": "OSGB36 / British National Grid"
		},
		"North West": { "zone": "BNG", "code": "EPSG:27700", "name": "OSGB36 / British National Grid" },
		"North East": { "zone": "BNG", "code": "EPSG:27700", "name": "OSGB36 / British National Grid" },
		"Highlands": { "zone": "BNG", "code": "EPSG:27700", "name": "OSGB36 / British National Grid" },
		"Central Belt": {
			"zone": "BNG",
			"code": "EPSG:27700",
			"name": "OSGB36 / British National Grid"
		},
		"Scottish Borders": {
			"zone": "BNG",
			"code": "EPSG:27700",
			"name": "OSGB36 / British National Grid"
		},
		"North Wales": {
			"zone": "BNG",
			"code": "EPSG:27700",
			"name": "OSGB36 / British National Grid"
		},
		"South Wales": {
			"zone": "BNG",
			"code": "EPSG:27700",
			"name": "OSGB36 / British National Grid"
		},
		"Mid Wales": { "zone": "BNG", "code": "EPSG:27700", "name": "OSGB36 / British National Grid" }
	}
}