<a href="http://insidebruegel.net" rel="nofollow">http://insidebruegel.net</a> does use OpenSeadragon. This normally comes with not-so-nice user interface buttons but has an excellent api so that it can be made to be as clever as what we have going on here.<p>I wish the site had more information on the paintings, the conventional art history. If anyone does have a very good source on individual Bruegel paintings then do share.<p><a href="https://openseadragon.github.io/" rel="nofollow">https://openseadragon.github.io/</a>