About 65 people, including Fr. Michael Pfleger, are making the trip.
The memorial will be dedicated on Sunday, which is also the same day that Hurricane Irene is forecasted to be impacting the Mid-Atlantic region. At this point, the ceremony is still on. The National ParkService says it's monitoring the forecast.
On Thursday, Attorney General Eric Holder will deliver remarks at an event leading up to the official dedication in Sunday.
ABC7's Cheryl Burton is in Washington for this historic event. Look for her reports starting at 10 p.m. Thursday.