Agapanthus.

Hard to say which variety without more detail as there are so many lighter blue ones.

Yes, a lovely Agapanthus..South African in origin I think. You get all shades of blue and white. It likes to have a warm sunny spot with it's roots restricted, so best grown in a pot. Mind you, I had one in my last garden in the soil but it was crammed up against a border edging and had tree roots close to it as well so it was happy. Some are hardier than others, so choose carefully :)

It needs good drainage, too--in a pot, I would use cactus mix. There are a few "hardy" varieties, but I don't know if they will be hardy enough to take a Pennsylvania winter, especially if away from the coast. Most would be indoor/outdoor plants.