Turin's understated elegance—all Savoy grandeur and Slow Food culture rather than gondola-clogged canals—makes it a refreshingly civilized landing point, but getting there in comfort requires strategy, since no carrier flies nonstop from St. Louis. There is no business class from St. Louis to Turin without at least one connection, and after dozens of iterations of this routing, I've settled on two reliable patterns: Delta via Amsterdam or Paris, or Lufthansa through Frankfurt or Munich, with Alitalia's successor ITA (still coded AZ in some booking systems) offering a Rome connection for those willing to add a short domestic hop. Total journey time from STL runs close to 15-16 hours door to door once you factor in the connection, though the long-haul segment itself is roughly 10.5 hours.
My preference leans toward Lufthansa's Frankfurt connection when their newer Allegris cabin is in rotation on the transatlantic leg—the suite doors and adjustable panels make a real difference on a red-eye, though not every aircraft has been retrofitted yet, so it's worth checking your specific tail number before booking. Delta's Amsterdam routing pairs nicely with their A330-900 or A350 business class, both featuring the reverse-herringbone seats with direct aisle access that have become the industry standard for comfort. If Munich is your connection, budget extra time; the walk between terminals for a tight layover is longer than it looks on paper, and Lufthansa's Munich lounges reward those with 90+ minutes to spare.
Insider tip: booking the STL-Turin routing through Rome on ITA, even with the extra domestic segment, often opens up better business class award availability than the more obvious northern European gateways, since Americans overlook it. January through March and again in October and November are consistently the softest months for premium fares on this corridor, as Turin's business and automotive trade traffic thins out. Given how much these fares swing week to week across three different alliances, setting up automated fare alerts for this specific routing is the smartest move you can make before committing to dates.