Boston boasts lots of excellent museums, and that’s a good thing since depending on the time of year you’re visiting, you might very well want to find an indoor activity to hide from the weather. You’ll find the Museum of Science on every list like this and for good reason. While some of the exhibits are a tad musty, the museum has modernized nicely overall, rotates fresh exhibits regularly, and its lightning exhibit featuring “the world's largest air-insulated Van de Graaff generator” never disappoints. Planetarium and IMAX theatre tickets cost extra. You can make a day of it here.