How do I set up a clickable image map?

There are really two issues here: how to indicate in HTML that you want an image to be clickable, and how to configure your server to do something with the clicks returned by Mosaic, Chimera, and other clients capable of delivering them.

You can read about image maps and the NCSA server at <URL:> ). Also see Joseph Walker's collection of imagemap resources (URL is <URL: > ).

Using imagemaps requires that you create a map file; you can do this by hand or with a WYSIWYG tool.

VERY IMPORTANT: Creating imagemaps requires a real web server (not an FTP server) and a cooperative web server administrator. It is not usually as simple as wrapping a link around an IMG SRC tag and adding the ISMAP directive; the server must also be told about the map file, and the way to accomplish this varies from server to server. So read your server documentation, and don't waste time making maps before making sure you have the necessary tools to deliver them.

Addendum: there are now web servers that actually do make it that simple; yours may be one of them. But if you have difficulties, TALK TO YOUR ADMIN AND READ YOUR SERVER MANUAL FIRST (really!) before posting.

Map THIS (URL is: is a feature-laden WYSIWYG imagemap editing tool for Microsoft Windows 32-bit environments (Win32s, Windows 95 or Windows NT required; Win32s is available from Microsoft's FTP site,, among other places). Free.
Web Hotspots
Web Hotspots (URL is <URL:> ) is a feature-rich imagemap editor for all Windows sytems, supporting zoom, advanced shape manipulation, and multiple-document interface. Shareware.
HoTTmapP Another WYSIWYG imagemap editor for Windows. Features permanent associations between images and map files for convenient reopening and manipulation of existing shapes. The capability to merge data from multiple MAPs is also provided. See <URL:> for more information.
Mapedit (URL is <URL:> ) is a simple WYSIWYG imagemap editing tool for both Microsoft Windows and the X Window System. Shareware.
For users of John Bradley's xv image display software for the X Window System, Mapmaker can turn the miniature images created by xv's Visual Schnauzer into an imagemap. This is useful if you would like to make an entire directory of images available (but note that you should also make textual links to allow those with text- based browsers to download the images for external viewing). (URL is: )
On the Macintosh, you may want to use MacMapMaker, available from <URL:> . It produces both NCSA and CERN-compatible maps, which can also be used with MacImagemap and a Macintosh-based server (MacImagemap is found in the same directory). There is another package available, called WebMap; however, the only FTP address I have for it points to an expired copy.
For Unix systems and other systems on which the Tk/Tcl language toolkit has been installed, Tkmapedit provides a WYSIWYG imagemap editor which is capable of directly testing links if the tkWWW web browser is available. Available by anonymous FTP from the TCL archive on
For Unix systems, glorglox is a unique imagemapping tool which allows color indexes in GIF images to be associated with URLs. It's easier to use this than to describe it (or pronounce it), so check out the glorglox home page (URL is <URL:> ).

World Wide Web FAQ