New Delhi, Aug. 2 -- The first time I saw Philadelphia's Reading Terminal Market, it wasn't in person; it was on the TV series Cold Case. In one memorable episode, the detectives emerged from the market, cheesesteaks in hand, biting into the city's most iconic sandwich as they discussed clues and suspects. The scene and the cavernous market with neon signage stuck with me.

Years later, when I finally walked through Reading Terminal's historic iron-framed doors, it was exactly as I imagined: an aromatic, sensory overload of sizzling grills, baking bread, spiced stews, and rows of fresh produce.

But the historical market is much more than a culinary centre point. The crowded aisles and colourful counters are a showcase of the layered food...