diff --git a/c/gtk3/fractal/fractal.c b/c/gtk3/fractal/fractal.c
new file mode 100644
index 0000000..bd64d81
--- /dev/null
+++ b/c/gtk3/fractal/fractal.c
@@ -0,0 +1,54 @@
+#include <math.h>
+#include <gtk/gtk.h>
+
+
+const double pi = 3.141592653589793;
+
+void line(cairo_t *cr, double x1, double y1, double x2, double y2) {
+  cairo_move_to(cr, x1, y1);
+  cairo_line_to(cr, x2, y2);
+  cairo_set_source_rgba(cr, 0, 0, 0, 1);
+  cairo_stroke(cr);
+}
+
+void figure(cairo_t *cr, double x1, double y1, double x2, double y2, int level) {
+  if (level < 5) {
+    double ax = (x2 - x1)/3 + x1;
+    double ay = (y2 - y1)/3 + y1;
+
+    double cx = (x1 - x2)/3 + x2;
+    double cy = (y1 - y2)/3 + y2;
+
+    double bx = (ax + cx)/2 + (cy - ay)*sin(60.0/180.0*pi);
+    double by = (ay + cy)/2 - (cx - ax)*sin(60.0/180.0*pi);
+
+    figure(cr, x1, y1, ax, ay, level+1);
+    figure(cr, ax, ay, bx, by, level+1);
+    figure(cr, bx, by, cx, cy, level+1);
+    figure(cr, cx, cy, x2, y2, level+1);
+  } else {
+    line(cr, x1, y1, x2, y2);
+  }
+}
+
+gboolean draw(GtkWidget *widget, cairo_t *cr, gpointer data) {
+  cairo_set_source_rgba(cr, 0.9, 0.9, 0.9, 1);
+  cairo_paint(cr);
+  figure(cr, 100, 400, 500, 400, 0);
+  return TRUE;
+}
+
+void activate(GtkApplication* app, gpointer data) {
+  GtkWidget *window = gtk_application_window_new (app);
+  g_signal_connect(window, "draw", G_CALLBACK(draw), NULL);
+  gtk_window_set_default_size(GTK_WINDOW(window), 600, 600);
+  gtk_widget_show_all(window);
+}
+
+int main(int argc, char **argv) {
+  GtkApplication *application = gtk_application_new(NULL, 0);
+  g_signal_connect(application, "activate", G_CALLBACK(activate), NULL);
+  int status = g_application_run(G_APPLICATION(application), argc, argv);
+  g_object_unref(application);
+  return status;
+}