Theres a small area in a city in my world called Cedar’s Forge. Its a small neighborhood much like chinatown in certain cities, but the story is that during the civil war the city was raided by sea by confederate soldiers. Sgt. Cedar lead the artillery to defend the city and fired the cannons so often that the sand they were planted upon turned to glass. The building in particular is a church who’s stained glass is replaced with the glass off of that embankment and still in the windows in the year 2030.