Logic Masters Deutschland e.V.

This puzzle is a combination of landvermessung, a fairly obscure genre, and U-Bahn. For a more approachable puzzle, try my previous puzzle with this ruleset, which can be found here.

Rules:

• U-Bahn: Draw a connected loop network through the centers of some cells, which may branch or turn, but may not have any dead ends.

  Clues to the left and above the grid indicates how many times the corresponding line shape (i.e. a cross, branch, straight line, or turn) appears in the corresponding row or column, irrespective of the line shape's rotation.

• Landvermessung: A clue in the centre of 4 cells gives the number of cells in the smallest possible loop which:

  1. Visits all those surrounding cells which are part of the network.

  2. Only uses segments from the network.

  3. Doesn't cross or overlap itself.

  An infinty symbol ∞ means that there is no such loop possible (but at least one of the surrounding cells must be part of the loop network).

For extra clarification, an example puzzle and it's solution are given. The example puzzle can be solved here. Main Puzzle:

Penpa+ link: Click Here