On Wednesday, District and national leaders will march through Washington’s monument core to kick off the 150th-anniversary celebration of a local holiday that marks the end of slavery in the nation’s capital.

D.C.’s Emancipation Day is officially April 16. But organizers have queued up a series of events all week to highlight the holiday’s impact on the area — other than, of course, giving local residents yet one more day to file their state and federal tax returns.