As advocates for the new Capitol Visitor Center for more than a decade, we are delighted with the structure, due to open Tuesday — with one exception. Emancipation Hall, renamed to honor slaves forced to help build the Capitol, contains not one image of an African-American.

Statues in the immense central space formerly known as the Great Hall commemorate several American Indians, including Sarah Winnemucca, the first Native American woman to publish a book, but not Martin Luther King Jr., Frederick Douglass or the Great Emancipator himself, Abraham Lincoln, who happens also to have been a Member of Congress.

CVC spokesmen say that the statue subjects in the Capitol are selected by the several states, not Congress, but the fact is that Emancipation Hall does contain a huge replica of the Statue of Freedom that tops the Capitol Dome, along with a single small placard referencing the role of “slave labor” in constructing the Capitol.

As we say, that flaw aside, the CVC is, as Rep. Debbie Wasserman Schultz (D-Fla.) put it, “a beautiful facility that is worthy of the Capitol.” It’s built of sandstone that matches closely the interior of the Capitol and is appointed with rich wood and dignified lighting.

We don’t know, or care, what architectural critics may say, but we’re sure that fiscal critics will greet the opening with guffaws about the CVC’s price tag — $621 million, six times its original estimate — and repeated construction delays.

Almost surely, as House appropriator Wasserman Schultz told Roll Call, the CVC would never have been built if Members and the public had known its final cost. And, the project was supposed to be completed for the 2005 presidential Inauguration, not the 2009.

But, as one of the facility’s other longtime backers, Rep. John Mica (R-Fla.), said, it’s still worth it. Mica’s original support in 1993 was based on providing a place for tourists to come in out of the rain and heat. The CVC fulfills that function grandly — and gives visitors a superb historical briefing on the Capitol, as well.

In July 1998, the CVC acquired a new rationale — security — when crazed gunman Russell Watson killed two Capitol policemen. And after Sept. 11, 2001, the facility required security upgrades that account for almost a quarter of its cost.

Over the years, we’ve joined in criticizing former Architect of the Capitol Alan Hantman for the project’s endless delays, and now it turns out he knew all along that stated deadlines would not be met but fibbed to keep support alive. We object to his deception, but we congratulate him on the accomplishment.

Essentially, he built a second Capitol, a 580,000-square-foot underground structure with a footprint larger than that of the Capitol itself. It’s not as beautiful as the Capitol — what could be? — but it honors the original.

Now, we appeal to Congress to complete the project. As the first African-American president is sworn in outside, surely there is a way to honor African-American emancipation inside.