EPSG:22994 — Egypt 1907 / Extended Purple Belt
Egypt 1907 / Extended Purple Belt (EPSG:22994) — a Projected (metres) system on the helmert datum, used in Egypt. Parameters, proj4, WKT, accuracy ±5 m, plus a free conv…
At a glance
- EPSG
- 22994
- Name
- Egypt 1907 / Extended Purple Belt
- Kind
- Projected (metres)
- Family
- Transverse Mercator (belt)
- Ellipsoid
- helmert
- Accuracy
- ±5 m (vs PROJ)
- Countries
- Egypt
Area of use
| West | 24.99° |
| South | 21.99° |
| East | 29.01° |
| North | 28.19° |
Projection parameters
| Projection | tmerc |
| Latitude of origin | 30 |
| Central meridian | 27 |
| Scale factor | 1 |
| False easting | 700000 |
| False northing | 1200000 |
| Ellipsoid | helmert |
| Units | m |
| Helmert shift to WGS84 | -130,110,-13,0,0,0,0 |
+proj=tmerc +lat_0=30 +lon_0=27 +k=1 +x_0=700000 +y_0=1200000 +ellps=helmert +units=m +no_defs +towgs84=-130,110,-13,0,0,0,0
PROJCS["Egypt 1907 / Extended Purple Belt",GEOGCS["GCS_Egypt 1907 / Extended Purple Belt",DATUM["D_Helmert_1906",SPHEROID["Helmert_1906",6378200,298.3],TOWGS84[-130,110,-13,0,0,0,0]],PRIMEM["Greenwich",0],UNIT["Degree",0.0174532925199433]],PROJECTION["Transverse_Mercator"],PARAMETER["False_Easting",700000],PARAMETER["False_Northing",1200000],PARAMETER["Central_Meridian",27],PARAMETER["Scale_Factor",1],PARAMETER["Latitude_Of_Origin",30],UNIT["Meter",1],AUTHORITY["EPSG","22994"]]
Sample conversion
Centre of the area of use: WGS84 27.00000, 25.09000 → EPSG:22994 699842.971, 655886.304
Values are within ±5 m at the test point.
About the Transverse Mercator (belt) family
Egypt 1907 / Extended Purple Belt is a Transverse Mercator belt — a national or cadastral grid in metres, conformal (angles are preserved), with its own central meridian and scale factor. Egypt's Red/Purple/Blue belts, the Levant grids, and many Gulf cadastral systems are of this kind.
Two things decide whether your coordinates land correctly: the exact belt (central meridian) and the datum. Mixing a coordinate from one belt into another, or ignoring the datum shift to WGS 84, is the usual cause of a systematic offset in imported survey data.
Related systems
- EPSG:3355 — Egypt Gulf of Suez S-650 TL / Red Belt
- EPSG:4199 — Egypt 1930
- EPSG:4229 — Egypt 1907
- EPSG:4706 — Egypt Gulf of Suez S-650 TL
- EPSG:22991 — Egypt 1907 / Blue Belt
- EPSG:22992 — Egypt 1907 / Red Belt
- EPSG:32635 — WGS 84 / UTM zone 35N
- EPSG:32636 — WGS 84 / UTM zone 36N
Useful links: Converter · Batch converter · File converter · Country page
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FAQ
- What is EPSG:22994?
- It is the coordinate system “Egypt 1907 / Extended Purple Belt”, a Projected (metres) system in the Transverse Mercator (belt) family, identified worldwide by the code EPSG:22994.
- What datum does it use, and how accurate is it?
- It is based on the helmert ellipsoid and it carries Helmert parameters to WGS84. The residual at the test point is about ±5 m versus PROJ; for centimetre work use a geodetic adjustment service.
- Where is this system used?
- It is used in Egypt. This page shows its area of use as a coordinate rectangle above.
- How do I convert EPSG:22994 to WGS84?
- Use the free coordinate converter above (preloaded with this system) to convert to WGS84, UTM, or any other system, within a ±5 m residual.
You may also need: Arab-world coordinate converter · Surveying file format converter · Batch coordinate file converter
