Did you hear bells ring one at a time, at a slow pace? Were there just a few different pitches? Did they play the Westminster Chimes?
What you likely heard was a clock chime. A clock chime is a small set of medium to large bells, usually three to five, that play a simple melody to mark the time. The bells are automated, and they usually mark the time on the hour or in 15-minute increments.
The Westminster Chimes pattern is by far the most common melodic pattern to mark the time–it’s so ubiquitous that one rarely hears a different one in North America. In 1793 the melody was written for St. Mary the Great in Cambridge, England, but it was after its adoption by St. Stephen’s Tower in the Houses of Parliament in 1860 that spurred its spread throughout England, and then to other countries. The first bells to use the Westminster Chimes in the United States were in Trinity Episcopal Church in Williamsport, Pennsylvania.
These days, the automated bells are usually struck with electro-magnetic hammers mounted on the outside of the bells.
Clock chimes can be programmed to do more than mark the time. In Catholic churches, they often will sound the Angelus, a pattern of a single bell ringing three times, three times in a row, then followed by nine strokes. They can also toll a single bell for funerals, and sometimes, they can mimic a peal from the English change ringing tradition for celebratory occasions, like weddings.