One of the most significant cultural collections of 2-dimensional art (prints, drawings and paintings) in the world made its relatively silent debut online recently. The British Museum has spent more than 15 years gearing up for this moment.

In my opinion this is the equivalent of the commencement of NYPL or the Library of Congress online. Seriously, this is a vast treasure trove and once you've spent any time there you'll never bother returning to poor old BibliOdyssey.

The advanced search page is the best place to start (and bookmark) [there appears to be no real home page as such]. The size of the database is enormous. There are more than 13,000 satirical prints for instance. A free text search on 'London' produces a similar number. There are over one thousand prints by Albrecht Dürer. 'Ornament' returns more than three thousand images. Although the image sizes vary, most are at least close to screen size and there is no watermarking.
http://bibliodyssey.blogspot.com/2007/11/british-museum-print-database.html