One of my work related travels to Cork, Ireland, happened to place me there on St. Patrick's Day. Oddly, I was so focused on the trip and tasks at hand that I'd failed to note the date, and found it surprising to arrive at the factory and discover it practically vacant. It's a national holiday there, unlike the US. Once I addressed the more pressing demands of the day, I returned to Morrison's Island, one of the hotels Apple business travelers stayed at, which was in the heart of downtown Cork. The streets were packed, there'd just been a parade [which I'd unfortunately missed] and the pubs were even more packed then usual. I found a solo barstool in a random pub, nursed a Murphy's, and casually people watched. It was a great experience, and I reflect on it every year on this day.
For the record, Saint Patrick's Day is a Catholic feast day which celebrates Saint Patrick (386-493), the patron saint of Ireland. You can read all about Saint Patrick's Day on Wikipedia, as it's always enlightening to know the background of the holiday you're celebrating.
Cheers!