diff --git a/core/map.h b/core/map.h
index a701ba36f73..c8197639f20 100644
--- a/core/map.h
+++ b/core/map.h
@@ -38,7 +38,7 @@
 */
 
 // based on the very nice implementation of rb-trees by:
-// http://web.mit.edu/~emin/www/source_code/red_black_tree/index.html
+// https://web.archive.org/web/20120507164830/http://web.mit.edu/~emin/www/source_code/red_black_tree/index.html
 
 template <class K, class V, class C = Comparator<K>, class A = DefaultAllocator>
 class Map {
diff --git a/core/math/camera_matrix.cpp b/core/math/camera_matrix.cpp
index caf08c73791..e523621f578 100644
--- a/core/math/camera_matrix.cpp
+++ b/core/math/camera_matrix.cpp
@@ -294,8 +294,8 @@ Vector<Plane> CameraMatrix::get_projection_planes(const Transform &p_transform)
 
 	/** Fast Plane Extraction from combined modelview/projection matrices.
 	 * References:
-	 * http://www.markmorley.com/opengl/frustumculling.html
-	 * http://www2.ravensoft.com/users/ggribb/plane%20extraction.pdf
+	 * https://web.archive.org/web/20011221205252/http://www.markmorley.com/opengl/frustumculling.html
+	 * https://web.archive.org/web/20061020020112/http://www2.ravensoft.com/users/ggribb/plane%20extraction.pdf
 	 */
 
 	Vector<Plane> planes;
diff --git a/core/set.h b/core/set.h
index 81250068af8..b2c717880d7 100644
--- a/core/set.h
+++ b/core/set.h
@@ -39,7 +39,7 @@
 */
 
 // based on the very nice implementation of rb-trees by:
-// http://web.mit.edu/~emin/www/source_code/red_black_tree/index.html
+// https://web.archive.org/web/20120507164830/http://web.mit.edu/~emin/www/source_code/red_black_tree/index.html
 
 template <class T, class C = Comparator<T>, class A = DefaultAllocator>
 class Set {
diff --git a/modules/bullet/rigid_body_bullet.h b/modules/bullet/rigid_body_bullet.h
index 1e1bea846a2..c1e4bd999be 100644
--- a/modules/bullet/rigid_body_bullet.h
+++ b/modules/bullet/rigid_body_bullet.h
@@ -305,7 +305,7 @@ public:
 	void reload_axis_lock();
 
 	/// Doc:
-	/// http://www.bulletphysics.org/mediawiki-1.5.8/index.php?title=Anti_tunneling_by_Motion_Clamping
+	/// https://web.archive.org/web/20180404091446/http://www.bulletphysics.org/mediawiki-1.5.8/index.php/Anti_tunneling_by_Motion_Clamping
 	void set_continuous_collision_detection(bool p_enable);
 	bool is_continuous_collision_detection_enabled() const;
 
diff --git a/servers/audio/effects/audio_effect_pitch_shift.cpp b/servers/audio/effects/audio_effect_pitch_shift.cpp
index ca2a88f8582..25f3dd0fbd3 100644
--- a/servers/audio/effects/audio_effect_pitch_shift.cpp
+++ b/servers/audio/effects/audio_effect_pitch_shift.cpp
@@ -70,7 +70,7 @@
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice and this license appear in all source copies.
 * THIS SOFTWARE IS PROVIDED "AS IS" WITHOUT EXPRESS OR IMPLIED WARRANTY OF
-* ANY KIND. See http://www.dspguru.com/wol.htm for more information.
+* ANY KIND. See https://dspguru.com/wide-open-license/ for more information.
 *
 *****************************************************************************/
 
diff --git a/servers/physics_2d/broad_phase_2d_hash_grid.cpp b/servers/physics_2d/broad_phase_2d_hash_grid.cpp
index 1bbb50c9748..6dd19c2868a 100644
--- a/servers/physics_2d/broad_phase_2d_hash_grid.cpp
+++ b/servers/physics_2d/broad_phase_2d_hash_grid.cpp
@@ -673,7 +673,7 @@ public IEnumerable<Point3D> GetCellsOnRay(Ray ray, int maxDepth)
     // "A Fast Voxel Traversal Algorithm for Ray Tracing"
     // John Amanatides, Andrew Woo
     // http://www.cse.yorku.ca/~amana/research/grid.pdf
-    // http://www.devmaster.net/articles/raytracing_series/A%20faster%20voxel%20traversal%20algorithm%20for%20ray%20tracing.pdf
+    // https://web.archive.org/web/20100616193049/http://www.devmaster.net/articles/raytracing_series/A%20faster%20voxel%20traversal%20algorithm%20for%20ray%20tracing.pdf
 
     // NOTES:
     // * This code assumes that the ray's position and direction are in 'cell coordinates', which means