Historic.Place as a part of OpenStreetmap is a free project. Nobody needs to pay for using the data.
The server infrastructure however produces costs which we cover by donations, exclusively.
You may donate as follows:
A bank transfer to the following account:
IBAN: DE93 5519 0000 0415 9380 26
BIC: MVBM DE 55
Reason for transfer: Historic.Place(the reason is important because otherwise the money could not be attributed to our project)
PayPal electronic transfer:
Reason for transfer (Field "Zweck"): Historic.Place