ArchInform: Database of worldwide architecture including built and unrealized projects.
The Architect's Library. "Notable Books on Architectural Themes in the Vassar College Library."
Association of Architecture School Librarians Core Reference List. Libguide to the most important books in many areas relating to architectural research.
Building Green: all about green architecture, worldwide.
Circular Worlds.com: Links to websites displaying panoramic imagery.
DesignInform Research Guide No. 1: Internet Sources of Biographical Information.
Digital Imaging Project: Art historical images of sculpture and architecture by Mary Ann Sullivan, Bluffton University.
Emporis: "Locate buildings in every country around the world." Great place for getting the facts concerning a building.
Europeana: "Explore Europe's Cultural Connections."
Fortified Places. Site about bastioned fortifications.
Galinsky: "People Enjoying Buildings Worldwide." Site started by students at the Harvard Graduate School of Design. Descriptive and practical information about buildings.
Great Buildings Collection: Good source for plans and 3D models of well-known buildings.
Historic Illustrations of Art and Architecture. Public domain images available for free downloads. Good for plans and architectural drawings.
Inexhibit Museum Magazine. website dedicated to museum architecture and exhibition design.
Mimoa: Online Architecture Guide: "The world's modern architecture organised, mapped and waiting to be discovered by you."
Panoramic Earth: Panoramic views of cities and architecture around the world.
Project for Public Spaces. "The central hub of the global Placemaking movement, connecting people to ideas, expertise, and partners who share a passion for creating vital spaces."
Qantara: Mediterranean Heritage. "Aims to contribute to mutual understanding and dialogue among Mediterranean cultures by highlighting their cultural heritage."
Sacred Destinations: "Explore sacred sites, ancient wonders and religious places of the world."
Sites in 3D: Panoramic views of buildings in many different countries, including many Islamic sites.
Structurae: International Database and Gallery of Structures. Engineering focus.
Vitruvio. International architectural site covering all time periods. In Italian.