diff --git a/builtin/settingtypes.txt b/builtin/settingtypes.txt
index df4484750..ea0ca9992 100644
--- a/builtin/settingtypes.txt
+++ b/builtin/settingtypes.txt
@@ -1016,7 +1016,7 @@ mgflat_ground_level (Mapgen flat ground level) int 8
 mgflat_large_cave_depth (Mapgen flat large cave depth) int -33
 
 #    Controls width of tunnels, a smaller value creates wider tunnels.
-mgflat_cave_width (Mapgen flat cave width) float 0.2
+mgflat_cave_width (Mapgen flat cave width) float 0.09
 
 #    Terrain noise threshold for lakes.
 #    Controls proportion of world area covered by lakes.
@@ -1046,7 +1046,7 @@ mgflat_np_cave2 (Mapgen flat cave2 noise parameters) noise_params 0, 12, (67, 67
 [***Mapgen fractal]
 
 #    Controls width of tunnels, a smaller value creates wider tunnels.
-mgfractal_cave_width (Mapgen fractal cave width) float 0.2
+mgfractal_cave_width (Mapgen fractal cave width) float 0.09
 
 #    Choice of 18 fractals from 9 formulas.
 #    1 = 4D "Roundy" mandelbrot set.
@@ -1148,7 +1148,7 @@ mgvalleys_river_size (River Size) int 5
 mgvalleys_water_features (Water Features) int 0
 
 #    Controls width of tunnels, a smaller value creates wider tunnels.
-mgvalleys_cave_width (Cave width) float 0.2
+mgvalleys_cave_width (Cave width) float 0.09
 
 # Noise parameters
 [****Noises]
diff --git a/minetest.conf.example b/minetest.conf.example
index bdd28cda6..ff365466f 100644
--- a/minetest.conf.example
+++ b/minetest.conf.example
@@ -1316,7 +1316,7 @@
 
 #    Controls width of tunnels, a smaller value creates wider tunnels.
 #    type: float
-# mgflat_cave_width = 0.2
+# mgflat_cave_width = 0.09
 
 #    Terrain noise threshold for lakes.
 #    Controls proportion of world area covered by lakes.
@@ -1357,7 +1357,7 @@
 
 #    Controls width of tunnels, a smaller value creates wider tunnels.
 #    type: float
-# mgfractal_cave_width = 0.2
+# mgfractal_cave_width = 0.09
 
 #    Choice of 18 fractals from 9 formulas.
 #    1 = 4D "Roundy" mandelbrot set.
@@ -1482,7 +1482,7 @@
 
 #    Controls width of tunnels, a smaller value creates wider tunnels.
 #    type: float
-# mgvalleys_cave_width = 0.2
+# mgvalleys_cave_width = 0.09
 
 ##### Noises
 
diff --git a/src/mapgen_flat.cpp b/src/mapgen_flat.cpp
index 2c1715e61..cc120b580 100644
--- a/src/mapgen_flat.cpp
+++ b/src/mapgen_flat.cpp
@@ -82,7 +82,7 @@ MapgenFlatParams::MapgenFlatParams()
 	spflags          = 0;
 	ground_level     = 8;
 	large_cave_depth = -33;
-	cave_width       = 0.2;
+	cave_width       = 0.09;
 	lake_threshold   = -0.45;
 	lake_steepness   = 48.0;
 	hill_threshold   = 0.45;
diff --git a/src/mapgen_fractal.cpp b/src/mapgen_fractal.cpp
index 0951a0afa..a6ed18ae7 100644
--- a/src/mapgen_fractal.cpp
+++ b/src/mapgen_fractal.cpp
@@ -84,7 +84,7 @@ MapgenFractal::~MapgenFractal()
 MapgenFractalParams::MapgenFractalParams()
 {
 	spflags    = 0;
-	cave_width = 0.2;
+	cave_width = 0.09;
 	fractal    = 1;
 	iterations = 11;
 	scale      = v3f(4096.0, 1024.0, 4096.0);
diff --git a/src/mapgen_valleys.cpp b/src/mapgen_valleys.cpp
index 456e6aa1a..ce7a95329 100644
--- a/src/mapgen_valleys.cpp
+++ b/src/mapgen_valleys.cpp
@@ -143,7 +143,7 @@ MapgenValleysParams::MapgenValleysParams()
 	river_depth        = 4;  // How deep to carve river channels.
 	river_size         = 5;  // How wide to make rivers.
 	water_features     = 0;  // How often water will occur in caves.
-	cave_width         = 0.2;
+	cave_width         = 0.09;
 
 	np_cave1              = NoiseParams(0,     12,   v3f(61,   61,   61),   52534, 3, 0.5,   2.0);
 	np_cave2              = NoiseParams(0,     12,   v3f(67,   67,   67),   10325, 3, 0.5,   2.0);