diff --git a/12/12.py b/12/12.py
new file mode 100755
index 0000000..26d1f4a
--- /dev/null
+++ b/12/12.py
@@ -0,0 +1,68 @@
+#!/usr/bin/env python
+# 2021 - Advent Of Code - 11
+
+GRID_SIZE = 10
+
+
+def parse_file(file):
+    with open(file) as f:
+        return [x.strip() for x in f.readlines()]
+
+
+def explore_tree(current_node, visited, paths_list, gen):
+    possible_path = [c for c in connections if current_node in c.split('-')]
+    print(f'\n{gen} current_node: {current_node}\t possible path: {possible_path}')
+    print(f'{gen} visited: {visited}')
+
+    for path in possible_path:
+        print(f'{gen} exploring {path}')
+        new_visited = list(visited)
+        # check end
+        if 'end' in path:
+            visited.append('end')
+            paths_list.append(visited)
+            print(f'{gen} keeping path: {visited}')
+            continue
+
+        nodes = path.split('-')
+        if nodes[0] == current_node:
+            if nodes[1] not in visited or nodes[1].isupper():
+                print(f'{gen} destination: {nodes[1]}')
+                new_visited.append(nodes[1])
+                explore_tree(nodes[1], list(new_visited), paths_list, gen+1)
+            else:
+                print(f'{gen} removing dest: {nodes[1]}')
+        else:
+            if nodes[0] not in visited or nodes[0].isupper():
+                print(f'{gen} destination: {nodes[0]}')
+                new_visited.append(nodes[0])
+                explore_tree(nodes[0], list(new_visited), paths_list, gen+1)
+            else:
+                print(f'{gen} removing dest: {nodes[0]}')
+
+
+connections = parse_file('input.txt')
+print(f'connections: {connections}')
+
+points = set()
+for conn in connections:
+    p = conn.split('-')
+    points.add(p[0])
+    points.add(p[1])
+
+print(f'unique points: {points}')
+print()
+
+starting_positions = [c for c in connections if 'start' in c]
+ending_positions = [c for c in connections if 'end' in c]
+
+visited_nodes = ['start']
+all_path = []
+explore_tree('start', visited_nodes, all_path, 0)
+
+print()
+print(f'listing all paths')
+for p in all_path:
+    print(p)
+
+print(f'{len(all_path)} paths')
diff --git a/12/input.txt b/12/input.txt
new file mode 100644
index 0000000..101ce3a
--- /dev/null
+++ b/12/input.txt
@@ -0,0 +1,26 @@
+end-ry
+jf-jb
+jf-IO
+jb-hz
+jo-LM
+hw-end
+hw-LM
+hz-ry
+WI-start
+LM-start
+kd-jf
+xi-WI
+hw-jb
+hz-jf
+LM-jb
+jb-xi
+ry-jf
+WI-jb
+end-hz
+jo-start
+WI-jo
+xi-ry
+xi-LM
+xi-hw
+jo-xi
+WI-jf
diff --git a/12/input_example1.txt b/12/input_example1.txt
new file mode 100644
index 0000000..6fd8c41
--- /dev/null
+++ b/12/input_example1.txt
@@ -0,0 +1,7 @@
+start-A
+start-b
+A-c
+A-b
+b-d
+A-end
+b-end
diff --git a/12/input_example2.txt b/12/input_example2.txt
new file mode 100644
index 0000000..62cc714
--- /dev/null
+++ b/12/input_example2.txt
@@ -0,0 +1,10 @@
+dc-end
+HN-start
+start-kj
+dc-start
+dc-HN
+LN-dc
+HN-end
+kj-sa
+kj-HN
+kj-dc
diff --git a/12/input_example3.txt b/12/input_example3.txt
new file mode 100644
index 0000000..65f3833
--- /dev/null
+++ b/12/input_example3.txt
@@ -0,0 +1,18 @@
+fs-end
+he-DX
+fs-he
+start-DX
+pj-DX
+end-zg
+zg-sl
+zg-pj
+pj-he
+RW-he
+fs-DX
+pj-RW
+zg-RW
+start-pj
+he-WI
+zg-he
+pj-fs
+start-RW