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What territory did Prussia lose in the Treaties of Tilsit?

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Historical map showing the unification of Germany by Prussia in the late 19th century. The map highlights in green the Kingdom of Prussia as of 1866, and in yellow the additional territories that formed the German Empire by 1871-1918, encompassing most of north-central Europe. Neighboring countries such as France, Belgium, the Netherlands, Denmark, Sweden, Russia, Austria-Hungary, and Switzerland are labeled, with major regions and states within the empire clearly marked. — Prussia The unification of Germany by Prussia, which brought most of north-central Europe into one kingdom.

Under the Treaties of Tilsit (1807), Prussia was forced to cede significant portions of its territory, effectively reducing the state to half of its former population. The territorial losses included:12

Western Territories: Prussia ceded all of its possessions located west of the Elbe River. These lands were primarily distributed to the newly created kingdom of Westphalia and the grand duchy of Berg, while East Frisia was ceded to Holland.12
Polish Territories: Prussia lost almost all territory it had acquired during the three Partitions of Poland. Specifically, it surrendered all lands gained in the Second and Third Partitions, along with the southern portion of its acquisitions from the First Partition. These areas were largely incorporated into the Duchy of Warsaw.123
Danzig: The city of Danzig (now Gdańsk, Poland) was removed from Prussian control and established as a free city under French garrison.12