Gold Mine Tunnel
================

+-- Ground level -----------------------------------------------------------------------+
|                                                                                       |
|               *--*--*     C                                   *                       |
|              /       \   /                                   / \                      |
|             /         \ /                                   /   \                     |
|            *           *                                   *     *                    |
|           /                                               /      |                    |
|          /                                               /       |                    |
|         *                                               *        *                    |
|         |                                               |         \                   |
|         |              ^                                |          \                  |
|         *           *--%--*                             %           *                 |
|        / \         /       \                            v           |                 |
|       /   \       /         \                                       |                 |
|      *     *--*--*           *                                C     *                 |
|     /        /               |                                |     |                 |
|    /        /                |                                |  ^  |                 |
|   *        *                 *                                *--C  *                 |
|   |        |                /                                /      |                 |
|   |        |               /                                /       |                 |
|   *        *              *                             *--*        *                 |
|   |        |              |                            /           /                  |
|   |        |              |                           /           /                   |
|   *        *--*           *                          *        *--*                    |
|   |            \         /                           |       /                        |
|   |             \       /                            |      /                         |
|   *              *     *                             *     *                          |
|    \             |      \                           /     /                           |
|     \            |       \                         /     /                            |
|      *--*        *        *                       *     *                             |
|          \       |        |                       |     |                             |
|           \      |        |                       |     |                             |
|            *     *        *                       *     *                             |
|            |     |       /                        |    /                              |
|            |     |      /                         |   /                               |
|            *     *     *                          *  *                                |
|            |     |     |                         /   |                                |
|            |     |     |                        /    |                                |
|            C     *     *                       *     *                                |
|                 /       \                      |    /                                 |
|                /         \                     |   /                                  |
|               *           *                    *  *                                   |
|               |            \                  /    \                                  |
|               |             \                /      \                                 |
|               *              *              *        *                                |
|                \             |             /|        |                                |
|                 \            |            / |        |                                |
|                  *--*        *--*--*--*--*  *        *                                |
|                      \                       \        \                               |
|                       \                       \        \                              |
|                        *--*                    *        *                             |
|                            \                    \        \                            |
|                             \                    \        \                           |
|                              *                    *        *                          |
|                               \                  / \        \                         |
|                                \                /   \        \                        |
|                     *--*--*     *--*           *     *        *                       |
|                    /       \        \          |      \        \                      |
|                   /         \        \         |       \        \                     |
|                  *           *        *        *        *        *                    |
|                 /             \        \       |        |        |                    |
|                /               \        \      |        |        |                    |
|               *                 *        *     *        *        *--*--*              |
|               |                 |        |      \        \       |      \             |
|               |                 |        |       \        \      |       \            |
|               *        *--*     *        *        *        *     *        *--*        |
|               |       /   |      \       |        |        |     |            \       |
|               |      /    |       \      |        |        |     |             \      |
|               *     *     *        *     *        *        *     *              *     |
|               |     |     |         \   /        /         |     |               \    |
|               |     |     |          \ /        /          |     |                \   |
|               *     *     *           *        *           *     *        C        *  |
|               |     |     |           |        |            \    |        |        |  |
|               |     |     |           |        |             \   |        |        |  |
|               *     *     *           *        *              *  *        *        *  |
|                \   /       \          |        |             /   |       /         |  |
|                 \ /         \         |        |            /    |      /          |  |
|                  *           *        *        *           *     *     *           *  |
|                   \           \       |         \         /      |     |           |  |
|                    \           \      |          \       /       |     |           |  |
|                     *           C     *           C     C        *     *           *  |
|                     |                 |                         /      |          /   |
|                     |                 |                        /       |         /    |
|                     *                 *                       *        *        *     |
|                      \                |                      /          \      /      |
|                       \               |                     /            \    /       |
|                        *              *                 *--*           *--*--*        |
|                         \              \               /              /               |
|                          \              \             /              /                |
|                           *--*           *--*--*--*--*           C--*                 |
|                               \         /                                             |
|                                \       /                                              |
|                                 *--*--*                                               |
|                                                                                       |
+---------------------------------------------------------------------------------------+

+-- Level -1 ---------------------------------------------------------------------------+
|                                                         ^                             |
|                                                         %                             |
|                                                         v                             |
|                                                                                       |
+---------------------------------------------------------------------------------------+

+-- Level -2 ---------------------------------------------------------------------------+
|                                                         ^                             |
|                                                         %                             |
|                                                         v                             |
|                                                                                       |
+---------------------------------------------------------------------------------------+

+-- Level -3 ---------------------------------------------------------------------------+
|                                                         ^                             |
|                                                         %                             |
|                                                         v                             |
|                                                                                       |
+---------------------------------------------------------------------------------------+

+-- Level -4 ---------------------------------------------------------------------------+
|                                                         ^                             |
|                                                         %                             |
|                                                         v                             |
|                                                                                       |
+---------------------------------------------------------------------------------------+

+-- Level -5 ---------------------------------------------------------------------------+
|                                                         ^                             |
|                                                         %                             |
|                                                         v                             |
|                                                                                       |
+---------------------------------------------------------------------------------------+

+-- Level -6 ---------------------------------------------------------------------------+
|                                                         ^                             |
|                                                         %                             |
|                                                         v                             |
|                                                                                       |
+---------------------------------------------------------------------------------------+

+-- Level -7 ---------------------------------------------------------------------------+
|                                                         ^                             |
|                                                         %                             |
|                                                         v                             |
|                                                                                       |
+---------------------------------------------------------------------------------------+

+-- Level -8 ---------------------------------------------------------------------------+
|                                                         ^                             |
|                                                         %                             |
|                                                         v                             |
|                                                                                       |
+---------------------------------------------------------------------------------------+