Le Jacob van Heemskerck est un croiseur de la défense côtière des Pays-Bas construit en 1905-1906 par le chantier NSM à Amsterdam. Ce navire de 4920 tonnes, de 98m par 15,19m, faisait ses 16,5 nœuds grâce à ses 6400cv répartis sur deux hélices.
Jacob van Hemskerck. On August 15, 1905 at Empire Shipyard in Amsterdam on staple and put on 23 September, 1906 by HRH Prince Hendrik water left. Dimensions: 98x15.20x5.70 m, 5000 tonnes of which, 6400IPK, 16.5 miles, 2 screws. Armament: 2 guns of 24 cm, 6 cm of 15 guns, 6 guns of 7.5 cm, 4 guns of .7 cm, 2 torpedo tubes. Crew 355. Armor: belt 150-100 mm, 200 mm artillery towers, commandotren 200 mm, 50 mm deck. Salvage 423 tonnes of coal. The cost of the ship in original equipment into the sea amounted to approximately f. 4660000. In service to Amsterdam on April 22, 1908.
HRMS Jacob van Heemskerck exercise regularly made trips on the North Sea, Atlantic Ocean, Mediterranean Sea, Norwegian and Danish waters, Baltic, in Curacao. On May 17, 1910 of Ijmuiden left with Prince Henry on board to Engelandd for the funeral of King Edward VII. From June 17 to June 29, 1911 a trip to Spit Head to attend the Fleet Review on the occasion celebrations of the coronation of English koningspaar. From 12-17 August 1912 the ship made a trip to Antwerp Conscience to attend the celebrations. The king of the Belgians visited on board. On June 13, 1915 were passengers and 30 crew members of the Bay of Hato stranded Italian ss Bologna to sign and January 14 dav to Curacao brought ashore. The efforts to expeditiously bring the ship had no result. HRMS Jacob van Heemskerck stayed up to 27 May 1915 at Curacao, Bonaire, Aruba and Paramaribo and returned alternatively by means of Newport News and Horta on 2 July 1915 at Willemsoord. On 27 November 1919 the ship service was put to undergoing extensive breakdown services, whereupon Hr M Jacob van Heemskerck on 21 February 1923 in service put. On 24 September 1926 service and on realm yard at Willemsoord in breakdown service to do service on 2 May 1929 up to 16 October 1933. On 19 April 1939 became the ship in service as a battery chip " put; Ijmuiden". On 14 May 1940 at Ijmuiden by the crew to sink brought. Later lifted by the bezetter and transmitted to Amsterdam. To floating air aim battery " brought on 21 March 1941 of Amsterdam to keel and there cultivated; Undine". After the capitulation of Germany retrieved at will helmet port and cultivated on realm yard at Willemsoord to boardinghouse ship. On 25 February 1948 as a boardinghouse ship " Neptunus" put in Den Helder in service.