diff --git a/src/sand-wedge-data/mygrid.cc b/src/sand-wedge-data/mygrid.cc
index d4fa12eac3ab5968ef80af8c7a49c55400d4e2a7..b2e9565312f25e553ed0f6fca80469ccabf1f799 100644
--- a/src/sand-wedge-data/mygrid.cc
+++ b/src/sand-wedge-data/mygrid.cc
@@ -52,7 +52,17 @@ template <class Grid> class GridConstructor {
     auto const &B = MyGeometry::B;
     auto const &C = MyGeometry::C;
 
-    unsigned int const vc = 3;
+    auto const AB = midPoint(A, B);
+    auto const AC = midPoint(A, C);
+    auto const BC = midPoint(B, C);
+
+    auto const AAB = midPoint(A, AB);
+    auto const AAC = midPoint(A, AC);
+    auto const ABB = midPoint(AB, B);
+    auto const ABC = midPoint(AB, C); // the interiour point
+    auto const ACC = midPoint(AC, C);
+
+    unsigned int const vc = 11;
 
 #if DIM == 3
     Dune::FieldMatrix<double, 2 * vc, DIM> vertices;
@@ -62,12 +72,28 @@ template <class Grid> class GridConstructor {
     for (size_t i = 0; i < 2; ++i) {
       size_t k = 0;
       vertices[k++][i] = A[i];
+      vertices[k++][i] = AAB[i];
+      vertices[k++][i] = AB[i];
+      vertices[k++][i] = ABB[i];
       vertices[k++][i] = B[i];
+      vertices[k++][i] = AAC[i];
+      vertices[k++][i] = AC[i];
+      vertices[k++][i] = ABC[i];
+      vertices[k++][i] = BC[i];
+      vertices[k++][i] = ACC[i];
       vertices[k++][i] = C[i];
       assert(k == vc);
 #if DIM == 3
       vertices[k++][i] = A[i];
+      vertices[k++][i] = AAB[i];
+      vertices[k++][i] = AB[i];
+      vertices[k++][i] = ABB[i];
       vertices[k++][i] = B[i];
+      vertices[k++][i] = AAC[i];
+      vertices[k++][i] = AC[i];
+      vertices[k++][i] = ABC[i];
+      vertices[k++][i] = BC[i];
+      vertices[k++][i] = ACC[i];
       vertices[k++][i] = C[i];
       assert(k == 2 * vc);
 #endif
@@ -95,7 +121,16 @@ template <class Grid> class GridConstructor {
 #else
     SimplexManager sm;
 #endif
-    sm.addFromVertices(0, 1, 2);
+    sm.addFromVertices(1, 5, 0);
+    sm.addFromVertices(1, 6, 5);
+    sm.addFromVertices(2, 6, 1);
+    sm.addFromVertices(7, 6, 2);
+    sm.addFromVertices(7, 2, 3);
+    sm.addFromVertices(7, 3, 8);
+    sm.addFromVertices(7, 8, 10);
+    sm.addFromVertices(7, 10, 9);
+    sm.addFromVertices(7, 9, 6);
+    sm.addFromVertices(8, 3, 4);
     auto const &simplices = sm.getSimplices();
 
     // sanity-check choices of simplices