BOSTON — The Leventhal Map & Education Center is a not-for-profit housed in the Boston Public Library with a mission of inspiring “curiosity and learning” through geographic perspectives.

The Boston Marathon, one of the World's Major Marathons, will be run on April 21st for the 129th time. Participants will enjoy many historic sights along the way.

For a historic city like Boston, arguments about preserving the past are a local pastime, but a string of new proposals are putting the battle between preservation and development front and center.