Meet your guide inside the Great Hall of Union Station, a masterpiece of Beaux-Arts architecture. We'll examine the monumental limestone columns and vaulted ceiling. Get an introduction to the history and sheer scale of the PATH system before descending into the modern transit network, to begin our underground journey.

Walk through the original 1927 tunnel - a pioneering feat of early subterranean engineering - connecting the transit hub to this historic hotel. Find out about the Chateauesque architectural style that defined Canada's early railway hotels and the structural dominance the Royal York once held over the Toronto skyline.

Navigate east to Brookfield Place and step into the breathtaking Allen Lambert Galleria. Designed by renowned architect Santiago Calatrava, this "crystal cathedral of commerce" is a stunning example of structural expressionism. We'll discuss how its biomorphic, bone-like steel ribs and vaulted glass canopy create a spectacular, light-filled gateway to the financial core.

We'll take a brief ride up to Front Street for a breath of fresh air and a look at Toronto's sports culture. You'll view famous bronze statues, including the 17-foot "Our Game," set against the Rococo exterior of the 1885 Bank of Montreal building. Heading back into the PATH, we'll walk the archival hallway to view the structural base of the historic bank vault that now safeguards hockey's greatest trophies.

Arrive at the epicenter of Canadian wealth. At this subterranean crossroads, we'll unpack the historic "MINT" acronym (Bank of Montreal, Imperial Bank, Bank of Nova Scotia, and Toronto Bank). Compare the heritage stonework of the previous stop with the sleek, glass-and-steel towers looming directly above, such as the iconic TD Centre.

We'll explore the hubs around Metro Hall and the sweeping glass canopy of Roy Thomson Hall. Examine how the PATH's urban planning safely and warmly funnels thousands of theatergoers directly into the subterranean lobbies of Toronto's premier performing arts venues.

Emerge from the underground maze at Toronto City Hall. We'll discuss the stark, intentional contrast between the heavy, 19th-century Romanesque Revival style of Old City Hall and the mid-century futurism of the New City Hall. Then watch Toronto come to life at the Nathan Philips Square.