Johann Gregor Memhardt (1607 - 1678) (or Memhard) was a German architect, landscape designer, military engineer, and politician. Memhardt emigrated from Linz to the Netherlands in 1622, where he probably learned the art of fortification. He served as a military engineer with George William, Elector of Brandenburg from 1638 onwards and in 1641 was appointed court engineer. Under his leadership the Residenzschloss was repaired and a chapel built for crown princess Louise Henriette. In the Lustgarten he built a 'Lusthaus'. From 1651 the Schloss Oranienburg and its gardens were built to Memhardt's designs, known from the plan of Berlin published in 1652. It is this plan for which, in cartographic circles, he is best known. It is the earliest printed map of Berlin.