Read their proposal story:
Some of Dan's friends were planning a trip to a beach house in Massachusetts and Dan decided that would be where he pulled the trigger (he had already had the ring for a few months and he was getting dangerously close to spilling the beans). Sarah almost figured it out when Dan suggested they buy new outfits for the trip and insisted on getting up for sunrise at a nearby lighthouse. One of Sarah's friends, Katherine, was key in shaking Sarah off the trail; "Dan likes clothes and hasn't bought any since he started working from home, and you like cheesy pictures."
They drove up to Mass on Saturday, when Sarah realized that she chipped her new nail polish, Dan deadpan looked at her and said, "Well its not like anybody is going to be looking at your hands," and the conversation ended.
The next morning, they woke up at 4:30 to get ready for pictures - the sun rose about 30 minutes sooner in Mass than it did in Baltimore. After taking a bunch of snaps, Dan went to get the ring from his back pocket, but the ring box got stuck. Sarah looked on like he was a crazy person as he jumped up and down trying to find an angle where his pants would allow the box to escape. "My wallet is twisted in my pocket and it feels super annoying!" and she bought the excuse! He freed the ring, got down on one knee, where she quickly joined him and said, "yes."