Toronto's historic Union Station, after years of neglect and decay, is undergoing a much-needed revitalization.

The architects have decided to keep much of the original train shed intact, but a large central section of the original structure has been torn down to make way for an airy, modern glass atrium.

With a huge chunk of the roof gone, the steel and concrete of the 86-year-old structure is juxtaposed against the gold-plated towers of Bay Street.

The contrast between the dark, heavy 1920s train shed and the new glass one is striking, to say the least.

Signs of decay are everywhere- there's not a girder or conduit in the entire place that isn't showing at least a hint of rust, flaking paint or hasty jury-rigging.

It will likely be a long while yet before the work is done.