On the Museum Boppard website, find information about the 'Adlerstein' (Eagle Stone). Explain its historical significance, including the year of the event it signifies and to whom the territory was transferred. Also, state what the 'Adlersteine' generally marked around Boppard.
Navigate to the 'Museumsrundgang' page. Click on the 'Stadtgeschichte' section. Expand the 'Seiteninhalt' to reveal sub-sections. Click on the 'Kurze Geschichte der Stadt Boppard' link. Locate the 'Adlerstein' section. Extract the historical significance, the year, the recipient of the territory transfer, and what the 'Adlersteine' generally marked.
State that the 'Adlersteine' marked the entire border around Boppard. Explain that they signify the transfer of the narrower 'Fiskus Boppard' (Boppard fiscal territory). Identify the year of transfer as 1312. Specify that the territory was transferred to the 'Trierer Erzbischof und Kurfürsten Balduin von Luxemburg' (Archbishop and Elector Balduin of Luxembourg of Trier).