17 files changed, 22 insertions, 44 deletions
diff --git a/CMakeLists.txt b/CMakeLists.txt
index a39cb5c..41da94f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -37,7 +37,6 @@ set(CPACK_SOURCE_INSTALLED_DIRECTORIES
     "${CMAKE_CURRENT_SOURCE_DIR}/uk_os/" "."
     "${CMAKE_CURRENT_SOURCE_DIR}/us_nga/" "."
     "${CMAKE_CURRENT_SOURCE_DIR}/us_noaa/" "."
-    "${CMAKE_CURRENT_SOURCE_DIR}/us_usgs/" "."
 )
 
 include(CPack)
diff --git a/README.DATUMGRID b/README.DATUMGRID
index cb4eeec..73d1b78 100644
--- a/README.DATUMGRID
+++ b/README.DATUMGRID
@@ -71,4 +71,3 @@ For example us_noaa for files originating from US NOAA.
 * [uk_os: UK OS](https://github.com/OSGeo/proj-datumgrid-geotiff/blob/master/uk_os/)
 * [us_nga: USA NGA](https://github.com/OSGeo/proj-datumgrid-geotiff/blob/master/us_nga/)
 * [us_noaa: USA NOAA](https://github.com/OSGeo/proj-datumgrid-geotiff/blob/master/us_noaa/)
-* [us_usgs: USA USGS](https://github.com/OSGeo/proj-datumgrid-geotiff/blob/master/us_usgs/)
diff --git a/us_usgs/FL.tif b/us_noaa/FL.tif
index fdc8813..08dac2c 100644
--- a/us_usgs/FL.tif
+++ b/us_noaa/FL.tif
diff --git a/us_usgs/MD.tif b/us_noaa/MD.tif
index 536ba98..234215c 100644
--- a/us_usgs/MD.tif
+++ b/us_noaa/MD.tif
diff --git a/us_noaa/README.us_noaa b/us_noaa/README.us_noaa
index a412a95..cb84fdb 100644
--- a/us_noaa/README.us_noaa
+++ b/us_noaa/README.us_noaa
@@ -5,6 +5,20 @@ from [US NOAA](https://www.ngs.noaa.gov)
 
 ## Included grids
 
+### USA: NAD27 -> NAD83
+
+*Source*: [.los/.las files coming from NOAA](https://www.ngs.noaa.gov/PC_PROD/NADCON/NADCON.zip)  
+*Format*: GeoTIFF converted from CTable2  
+*License*: Public Domain
+
+* alaska.tif - Alaska
+* conus.tif - Conterminous U.S.
+* hawaii.tif - Hawaii
+* prvi.tif - Puerto Rico, Virgin Is.
+* stgeorge.tif - St. George Is, Alaska
+* stlrnc.tif - St. Lawrence Is., Alaska
+* stpaul.tif - St. Paul Is., Alaska
+
 ### USA: NAD83 -> NAD83 (HARN/HPGN)
 
 *Source*: [.los/.las files coming from NOAA](https://www.ngs.noaa.gov/PC_PROD/NADCON/NADCON.zip)  
@@ -22,6 +36,14 @@ Those files have been converted to NTv2 grids with the
 
 * *hpgn.tif (51 files)
 
+Also include a few files which are duplicate of *hpgn.tif files, for historic reasons:
+
+* FL.tif - Florida
+* MD.tif - Maryland
+* TN.tif - Tennessee
+* WI.tif - Wisconsin
+* WO.tif - Washington, Oregon, N. California
+
 ### Continental USA VERTCON: NGVD (19)29 height to NAVD (19)88 height
 
 *Source*: converted from [NOAA VERTCON .94 grids](https://www.ngs.noaa.gov/PC_PROD/VERTCON/)  
diff --git a/us_usgs/TN.tif b/us_noaa/TN.tif
index 6b1a605..f46162e 100644
--- a/us_usgs/TN.tif
+++ b/us_noaa/TN.tif
diff --git a/us_usgs/WI.tif b/us_noaa/WI.tif
index 983134f..033b0a6 100644
--- a/us_usgs/WI.tif
+++ b/us_noaa/WI.tif
diff --git a/us_usgs/WO.tif b/us_noaa/WO.tif
index 3021db0..7719393 100644
--- a/us_usgs/WO.tif
+++ b/us_noaa/WO.tif
diff --git a/us_usgs/alaska.tif b/us_noaa/alaska.tif
index bd21d18..a11852a 100644
--- a/us_usgs/alaska.tif
+++ b/us_noaa/alaska.tif
diff --git a/us_usgs/conus.tif b/us_noaa/conus.tif
index ddefd9b..88c4d00 100644
--- a/us_usgs/conus.tif
+++ b/us_noaa/conus.tif
diff --git a/us_usgs/hawaii.tif b/us_noaa/hawaii.tif
index bd5edf8..ae42539 100644
--- a/us_usgs/hawaii.tif
+++ b/us_noaa/hawaii.tif
diff --git a/us_usgs/prvi.tif b/us_noaa/prvi.tif
index 8a73279..2aff41c 100644
--- a/us_usgs/prvi.tif
+++ b/us_noaa/prvi.tif
diff --git a/us_usgs/stgeorge.tif b/us_noaa/stgeorge.tif
index 1b6b70a..bea39ab 100644
--- a/us_usgs/stgeorge.tif
+++ b/us_noaa/stgeorge.tif
diff --git a/us_usgs/stlrnc.tif b/us_noaa/stlrnc.tif
index 8b6272c..2591aba 100644
--- a/us_usgs/stlrnc.tif
+++ b/us_noaa/stlrnc.tif
diff --git a/us_usgs/stpaul.tif b/us_noaa/stpaul.tif
index 49d7333..5ad9cc1 100644
--- a/us_usgs/stpaul.tif
+++ b/us_noaa/stpaul.tif
diff --git a/us_usgs/.github/README.md b/us_usgs/.github/README.md
deleted file mode 120000
index 50d9990..0000000
--- a/us_usgs/.github/README.md
+++ /dev/null
@@ -1 +0,0 @@
-../README.us_usgs
-\ No newline at end of file
diff --git a/us_usgs/README.us_usgs b/us_usgs/README.us_usgs
deleted file mode 100644
index 6de016e..0000000
--- a/us_usgs/README.us_usgs
+++ /dev/null
@@ -1,41 +0,0 @@
-# README.us_usgs
-
-The files in this section result from the conversion of datasets originating
-from USGS
-
-TODO: Aren't they coming from NOAA instead ?
-
-## Included grids
-
-### USA: NAD27 -> NAD83
-
-*Source*: USGS  
-*Format*: GeoTIFF converted from CTable2  
-*License*: Public Domain
-
-* alaska.tif - Alaska
-* conus.tif - Conterminous U.S.
-* hawaii.tif - Hawaii
-* prvi.tif - Puerto Rico, Virgin Is.
-* stgeorge.tif - St. George Is, Alaska
-* stlrnc.tif - St. Lawrence Is., Alaska
-* stpaul.tif - St. Paul Is., Alaska
-
-### USA: NAD83 -> NAD83 (HARN/HPGN)
-
-*Source*: USGS
-*Format*: GeoTIFF converted from CTable2
-*License*: Public Domain
-
-Grid data for high precision conversion of geographic coordinates from
-the original NAD83 (1986) (EPSG:4269) to NAD83 High Precision Geodetic Networks
-(HPGNs) (EPSG:4152), also referred to as High Accuracy Reference Networks (HARNs).
-NAD 83 coordinates based on the HPGN/HARN surveys changed approximately 0.2
-to 1.0 meter relative to the original NAD 83 (1986) adjustment.
-
-* FL.tif - Florida
-* MD.tif - Maryland
-* TN.tif - Tennessee
-* WI.tif - Wisconsin
-* WO.tif - Washington, Oregon, N. California
-