Metered to 8 mins @ stock speed, corrected to Ei 6 to compensate for reciprocity failure.
While the shutter was open, 2 city busses, 3-4 taxis and a security guard passed by without leaving even the slightest trace on the film, hooray for long exposures!
That's a remarkable piece of architecture. And well done for having the patience to hang around for a 24 minute exposure. The longest I've ever done is 3 minutes and even that got on my nerves.