diff --git a/libraries/AP_Terrain/AP_Terrain.cpp b/libraries/AP_Terrain/AP_Terrain.cpp
index 229469fb21..7159bda9ca 100644
--- a/libraries/AP_Terrain/AP_Terrain.cpp
+++ b/libraries/AP_Terrain/AP_Terrain.cpp
@@ -14,12 +14,12 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <AP_HAL.h>
-#include <AP_Common.h>
-#include <AP_Math.h>
-#include <GCS_MAVLink.h>
-#include <GCS.h>
-#include <DataFlash.h>
+#include <AP_HAL/AP_HAL.h>
+#include <AP_Common/AP_Common.h>
+#include <AP_Math/AP_Math.h>
+#include <GCS_MAVLink/GCS_MAVLink.h>
+#include <GCS_MAVLink/GCS.h>
+#include <DataFlash/DataFlash.h>
 #include "AP_Terrain.h"
 
 #if AP_TERRAIN_AVAILABLE
diff --git a/libraries/AP_Terrain/AP_Terrain.h b/libraries/AP_Terrain/AP_Terrain.h
index cd51014dc6..91e5a48f0a 100644
--- a/libraries/AP_Terrain/AP_Terrain.h
+++ b/libraries/AP_Terrain/AP_Terrain.h
@@ -17,9 +17,9 @@
 #ifndef __AP_TERRAIN_H__
 #define __AP_TERRAIN_H__
 
-#include <AP_Common.h>
-#include <AP_HAL.h>
-#include <DataFlash.h>
+#include <AP_Common/AP_Common.h>
+#include <AP_HAL/AP_HAL.h>
+#include <DataFlash/DataFlash.h>
 
 #if HAL_OS_POSIX_IO && defined(HAL_BOARD_TERRAIN_DIRECTORY)
 #define AP_TERRAIN_AVAILABLE 1
@@ -29,10 +29,10 @@
 
 #if AP_TERRAIN_AVAILABLE
 
-#include <AP_Param.h>
-#include <AP_AHRS.h>
-#include <AP_Mission.h>
-#include <AP_Rally.h>
+#include <AP_Param/AP_Param.h>
+#include <AP_AHRS/AP_AHRS.h>
+#include <AP_Mission/AP_Mission.h>
+#include <AP_Rally/AP_Rally.h>
 
 #define TERRAIN_DEBUG 0
 
diff --git a/libraries/AP_Terrain/TerrainGCS.cpp b/libraries/AP_Terrain/TerrainGCS.cpp
index 73e32f7cab..c3361d5c8d 100644
--- a/libraries/AP_Terrain/TerrainGCS.cpp
+++ b/libraries/AP_Terrain/TerrainGCS.cpp
@@ -17,11 +17,11 @@
   handle vehicle <-> GCS communications for terrain library
  */
 
-#include <AP_HAL.h>
-#include <AP_Common.h>
-#include <AP_Math.h>
-#include <GCS_MAVLink.h>
-#include <GCS.h>
+#include <AP_HAL/AP_HAL.h>
+#include <AP_Common/AP_Common.h>
+#include <AP_Math/AP_Math.h>
+#include <GCS_MAVLink/GCS_MAVLink.h>
+#include <GCS_MAVLink/GCS.h>
 #include "AP_Terrain.h"
 
 #if AP_TERRAIN_AVAILABLE
diff --git a/libraries/AP_Terrain/TerrainIO.cpp b/libraries/AP_Terrain/TerrainIO.cpp
index 7beee1a5c5..5b98f36606 100644
--- a/libraries/AP_Terrain/TerrainIO.cpp
+++ b/libraries/AP_Terrain/TerrainIO.cpp
@@ -17,11 +17,11 @@
   handle disk IO for terrain code
  */
 
-#include <AP_HAL.h>
-#include <AP_Common.h>
-#include <AP_Math.h>
-#include <GCS_MAVLink.h>
-#include <GCS.h>
+#include <AP_HAL/AP_HAL.h>
+#include <AP_Common/AP_Common.h>
+#include <AP_Math/AP_Math.h>
+#include <GCS_MAVLink/GCS_MAVLink.h>
+#include <GCS_MAVLink/GCS.h>
 #include "AP_Terrain.h"
 
 #if AP_TERRAIN_AVAILABLE
diff --git a/libraries/AP_Terrain/TerrainMission.cpp b/libraries/AP_Terrain/TerrainMission.cpp
index fbb7350c30..006a7f2480 100644
--- a/libraries/AP_Terrain/TerrainMission.cpp
+++ b/libraries/AP_Terrain/TerrainMission.cpp
@@ -17,11 +17,11 @@
   handle checking mission points for terrain data
  */
 
-#include <AP_HAL.h>
-#include <AP_Common.h>
-#include <AP_Math.h>
-#include <GCS_MAVLink.h>
-#include <GCS.h>
+#include <AP_HAL/AP_HAL.h>
+#include <AP_Common/AP_Common.h>
+#include <AP_Math/AP_Math.h>
+#include <GCS_MAVLink/GCS_MAVLink.h>
+#include <GCS_MAVLink/GCS.h>
 #include "AP_Terrain.h"
 
 #if AP_TERRAIN_AVAILABLE
diff --git a/libraries/AP_Terrain/TerrainUtil.cpp b/libraries/AP_Terrain/TerrainUtil.cpp
index 7e716af50d..96d94751c1 100644
--- a/libraries/AP_Terrain/TerrainUtil.cpp
+++ b/libraries/AP_Terrain/TerrainUtil.cpp
@@ -17,11 +17,11 @@
   handle disk IO for terrain code
  */
 
-#include <AP_HAL.h>
-#include <AP_Common.h>
-#include <AP_Math.h>
-#include <GCS_MAVLink.h>
-#include <GCS.h>
+#include <AP_HAL/AP_HAL.h>
+#include <AP_Common/AP_Common.h>
+#include <AP_Math/AP_Math.h>
+#include <GCS_MAVLink/GCS_MAVLink.h>
+#include <GCS_MAVLink/GCS.h>
 #include "AP_Terrain.h"
 
 #if AP_TERRAIN_AVAILABLE