M 19 mortar, U-boat base

A complete bunker for the automatic fortress mortar M19 was built on top of the U-Bootbunker. A second one was never finished.

It's a heavy version of the turret type 428P01 which is 420mm thick.

Close up, with left the opening for the mortar tube and right for the periscope.

One entrance is beneath the concrete beams.