Index: source/tools/atlas/AtlasUI/CustomControls/FileHistory/FileHistory.h
===================================================================
--- source/tools/atlas/AtlasUI/CustomControls/FileHistory/FileHistory.h
+++ source/tools/atlas/AtlasUI/CustomControls/FileHistory/FileHistory.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2012 Wildfire Games.
+/* Copyright (C) 2019 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -28,11 +28,7 @@
 	virtual void SaveToSubDir(wxConfigBase& config);
 
 private:
-#if wxCHECK_VERSION(2, 9, 0)
 	virtual void Load(const wxConfigBase& config)
-#else
-	virtual void Load(wxConfigBase& config)
-#endif
 	{
 		wxFileHistory::Load(config);
 	}
Index: source/tools/atlas/AtlasUI/CustomControls/MapDialog/MapDialog.h
===================================================================
--- source/tools/atlas/AtlasUI/CustomControls/MapDialog/MapDialog.h
+++ source/tools/atlas/AtlasUI/CustomControls/MapDialog/MapDialog.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2018 Wildfire Games.
+/* Copyright (C) 2019 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -19,11 +19,7 @@
 #define INCLUDED_MAPDIALOG
 
 #include <wx/dialog.h>
-#include <wx/version.h>
 
-#if !wxCHECK_VERSION(2, 9, 0)
-#define wxBookCtrlEvent wxNotebookEvent
-#endif
 class wxBookCtrlEvent;
 
 enum MapDialogType { MAPDIALOG_OPEN, MAPDIALOG_SAVE };
Index: source/tools/atlas/AtlasUI/Misc/precompiled.h
===================================================================
--- source/tools/atlas/AtlasUI/Misc/precompiled.h
+++ source/tools/atlas/AtlasUI/Misc/precompiled.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2015 Wildfire Games.
+/* Copyright (C) 2019 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -116,6 +116,11 @@
 # define ATLASDLLIMPEXP extern "C"
 #endif
 
+// wxWidgets 3.0 or later required
+#if !wxCHECK_VERSION(3, 0, 0)
+# error You are using an old wxWidgets release. At least wxWidgets >= 3.0.0 is required.
+#endif
+
 // Abort with an obvious message if wx isn't Unicode, instead of complaining
 // mysteriously when it first discovers wxChar != wchar_t
 #ifndef UNICODE
Index: source/tools/atlas/AtlasUI/ScenarioEditor/Tools/TransformObject.cpp
===================================================================
--- source/tools/atlas/AtlasUI/ScenarioEditor/Tools/TransformObject.cpp
+++ source/tools/atlas/AtlasUI/ScenarioEditor/Tools/TransformObject.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2015 Wildfire Games.
+/* Copyright (C) 2019 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -26,7 +26,6 @@
 #include <wx/clipbrd.h>
 #include <wx/xml/xml.h>
 #include <wx/sstream.h>
-#include <wx/version.h>
 
 using AtlasMessage::Position;
 
@@ -143,13 +142,8 @@
 				else if (xmlData->GetName() == wxT("Position"))
 				{
 					wxString x, z;
-#if wxCHECK_VERSION(3, 0, 0)
 					xmlData->GetAttribute(wxT("x"), &x);
 					xmlData->GetAttribute(wxT("z"), &z);
-#else
-					xmlData->GetPropVal(wxT("x"), &x);
-					xmlData->GetPropVal(wxT("z"), &z);
-#endif
 
 					double aux, aux2;
 					x.ToDouble(&aux);
@@ -160,11 +154,7 @@
 				else if (xmlData->GetName() == wxT("Orientation"))
 				{
 					wxString y;
-#if wxCHECK_VERSION(3, 0, 0)
 					xmlData->GetAttribute(wxT("y"), &y);
-#else
-					xmlData->GetPropVal(wxT("y"), &y);
-#endif
 					y.ToDouble(&orientation);
 				}
 				else if (xmlData->GetName() == wxT("Player"))