The John Hancock Tower which was designed by I.M. Pei & Partners in the early 1970s transformed Boston’s skyline and is often photographed by tourists and residents alike. The soaring glass structure literally reflects the Back Bay neighborhood. When the structure was being built, architects had an issue with the large reflective glass windows popping out and crashing below. Many of those patched windows in the photo from 1973 are from those falling windows. Pedestrians must’ve cast a weary eye toward the sky when walking by. The more recent photograph is of the same building but from a different angle to afford you a better appreciation for the minimalist design the building is noted for.