[1] It covered most part of the peninsula, and during Polish September Campaign, it was the last place of Poland to surrender to the invading Wehrmacht[2] (for more information, see Battle of Hel).

As early as 22 July 1920 General Kazimierz Sosnkowski ordered construction of a strategic rail line which ran from Puck, through Wladyslawowo, to Hel.

These regulations were strengthened by the decree of President Ignacy Mościcki, signed on 21 August 1936, which officially created the Hel Fortified Area.

An underground power plant was placed some 1.5 kilometers north of the port, also in adjacent forests, shelters for ammunition, mines and torpedoes were built.

In July 1935, four Swedish-made Bofors guns (152 mm) were bought and brought to Gdynia aboard transport ship ORP Wilia.

[6] Cut off from the mainland on 14 September and shelled with 280 millimeter guns, it surrendered on 1 October 1939 after a fierce defense, during which many German planes were shot down.

The Wehrmacht also installed Würzburg-Riese radar stations, as Hela was supposed to defend the main naval port of Gdynia, renamed Gotenhafen.

On the night of 3–4 April 1945, the Germans carried out Operation Walpurgisnacht, during which thousands of soldiers and refugees were transported from Gdynia to Hela.