You must turn on the browser location services to get the route from your current location to the sign, and the distance (as the crow flies) from your current location to the sign.
After activating location services, refresh the page.
On the sign:
Tower Bridge is provided by the City of London Corporation a uniquely diverse organisation in that not only promotes and supports the City and provides it with a full range of services but also provides wider services for London and the nation ad a whole.
CITY OF LONDON
Control Cabin
When it was first built, Tower Bridge was controlled from two cabins, situated on the east side of each pier. These were originally built of wood, but were replaced with stone structures after World War II. Since 1962, due to the decline in river traffic, any ships large enough to require the bascules to be raised have to give 24 hours’ notice.