Nestboxes in trees
http://www.flickr.com/photos/110581570@N03/11212234164/
http://www.flickr.com/photos/110581570@N03/11212451563/
http://www.flickr.com/photos/110581570@N03/11212339426/
http://www.flickr.com/photos/110581570@N03/11212450203/