colbert foundation, independent production fund, with support from the partridge foundation, john and pauley guthcharitable fund. clemens foundation. park foundation, dedicated to heightening public awareness of critical issues. the herb albert foundation, supporting organizations whose mission is to promote passion and creativity in our society. the bernard and audrey rapport foundation. john d. and katherine t. mcarthur foundation, committed to building a more just and peaceful world. more information at mac found.org. betsy and jesse fink foundation. the hkh foundation. barbara g. fleischman and our sole corporate sponsor, mutual of america, designing customized individual and group retirement product. that's why we're your retirement company.

colbert foundation, independent production fund, with support from the partridge foundation, john and pauley guthcharitable fund. clemens foundation. park foundation, dedicated to heightening public awareness of critical issues. the herb albert foundation, supporting organizations whose mission is to promote passion and creativity in our society. the bernard and audrey rapport foundation. john d. and katherine t. mcarthur foundation, committed to building a more just and peaceful world. more information at mac found.org. betsy and jesse fink foundation. the hkh foundation. barbara g. fleischman and our sole corporate sponsor, mutual of america, designing customized individual and group retirement product. that's why we're your retirement company. steves: pisa, in the north of italy, is a grand city with a grand history. for nearly three centuries, until about the year 1300, pisa was a booming port town, rivaling venice and genoa as a sea-trading power. from here, where the arno river meets the sea, its 150-foot galleys cruised most of the mediterranean. during the crusades, pisan ships transporte