Moving mouse over any building/sqaure will create a "popup" effect, by using .getBBox() to calcualte the cetner of each element and transforming + translating the element.
Clicking on a building/sqaure will change the number of the building to its name, using .innerHTML to change their respective text elements.
Clicking down on a buildig/sqaure will display a picture of the building, using .setAttributeNS() to change the href to its respective image.
Double clicking on a building/square will reset its text to its default and remove the image from the window, using the dblclick event listener to identify a double click
Holding on 'Mile End Road' text element will display the closest underground stations, used a combination of methods used for the previous points
Hovering around the map will complete the map by showing the other buildings in the area.