Zoom on a Map

Hey,

Does anyone have suggestions on the best approach for this project:

I would like to have a district map on a website which the user can view, however, I would like them to be able to zoom in on an area by mouse clicking in the map to be able to view the roads closer.

I was thinking of perhaps making a grid ontop of the map, and any time a user clicks a cell of the grid, I would tween between the zoomed section of the map and the original map.

If there might be a better way to get started on this project, let me know.

Thanks,

Ryan