President Obama paid homage Tuesday to those who had fought for women's equality, designating a historic house on Capitol Hill a national monument, and hinting that his successor could represent yet another victory for women's rights.

Speaking at the Sewall-Belmont House and Museum, which has housed the National Woman's Party since 1929 and will now be called the Belmont-Paul Women's Equality National Monument, the president called the site "a hotbed of activism, a centerpiece for the struggle for equality, a monument to a fight not just for women's equality but, ultimately, for equality for everybody."

"I have faith because what this house shows us is that the story of America is a story of progress," Obama said before a crowd of women's activists that included tennis legend Billie Jean King and Sen. Barbara A. Mikulski (D-Md.).

"I want young girls and boys to come here, 10, 20, 100 years from now, to know that women fought for equality, it was not just given to them," he said. "I want them to be astonished that there was ever a time when women earned less than men for doing the same work. I want them to be astonished that there was ever a time when women were vastly outnumbered in the boardroom or in Congress, that there was ever a time when a woman had never sat in the Oval Office."

The new designation honors both Alva Belmont, the National Woman's Party benefactor, and Alice Paul, who founded the party and served as its chief strategist. Obama made his announcement at the house, which served as the party's fifth headquarters, on Equal Pay Day, an annual commemoration that aims to highlight economic disparities between men and women. The date marks how many extra days a woman would have to work to make as much as a typical man would have made in the previous calendar year.

The president connected the fight for women's right to vote a century ago to the current push for higher compensation for women in the workforce, saying, "I’m not here just to say we should close the wage gap. I’m here to say we will close the wage gap. ... If you don’t believe that we’re going to close our wage gap, you need to come visit this house, because this house has a story to tell."

Obama has made equal pay for women a major policy platform. He has signed the Lilly Ledbetter Fair Pay Act, making it easier for women to sue for pay discrimination, and has issued executive orders prohibiting federal contractors from discriminating against employees who discuss or inquire about their compensation.

Located just yards away from the grounds of the Capitol and Supreme Court, and averaging about 10,000 visitors a year, the site will be managed by the National Park Service. The presidential proclamation designating the site said the tactics of Paul and her fellow party members "became a blueprint for civil rights organizations and activities throughout the 20th century. Today, the House tells the story of a century of courageous activism by American women."

The house itself was constructed around 1800 by Robert Sewall and was used by Treasury Secretary Albert Gallatin during the Jefferson administration. It serves as the site of the only resistance to the British invasion of Washington, during the War of 1812, and was set on fire by the British in retaliation. But Sewall had rebuilt it by 1820, and it remained in his family's possession for another century before it changed hands. There was an effort to tear the house down in the early 1970s when the Hart Senate Office Building was being built, according to the house and museum's executive director Page Harrington, but women lawmakers including then-Rep. Pat Schroeder (D-Colo.) defended it and got it declared a national landmark.

The National Woman's Party, which will be 100 years old in June, became an educational organization in 1997 and continues to educate the public on the issues of gender equality. The house contains the most complete collection of women’s suffrage and equal rights movement documents and artifacts in America, according to the National Parks Conservation Association, including almost 1,000 different textiles. The Florence Bayard Hilles Research Library, which houses the archival collection, was the nation's first feminist library.

Before speaking Obama had a chance to look at a few items from the collection, Harrington said, including one of the “Jail for Freedom” pins suffragists sported, an original floor-length purple and gold cape they wore in marches and a banner that asked Wilson, "Mr. President, what will you do for women’s suffrage?"

The banners, she added, provide a concrete link between the current day and the Americans who pressed their case more than a century ago. "Those were the ones that were snowed on, rained on and spit on, in some cases," Harrington said.

Although Paul is not well known, she played a pivotal role in the fight to win women's right to vote. She staged a 10-month picket at the White House to pressure President Woodrow Wilson on this issue: Sentenced to seven months in jail, Paul launched a hunger strike along with other activists to protest miserable prison conditions.

Paul skillfully played the harsh tactics of suffragists' opponents against them: When men — including some police officers — physically assaulted her group at a march during Wilson's 1913 inauguration, she described it later in a letter as “probably the best thing that could ever have happened to us” because “it aroused a great deal of public indignation and sympathy.”

Kristen Brengel, vice president of government affairs for the National Parks Conservation Association, said in an email that Paul's index card-based lobbying system, "where she recorded her notes on every member of Congress in great detail," serves as an inspiration for her own work in a totally different era.

"She was an incredible campaigner — deploying women all over the country to get their constituents to support the constitutional amendment," Brengel said.

Selecting a women's history site as his latest monument — Obama has now designated nearly two dozen of them, encompassing more than 265 million acres of U.S. lands and waters — reflects the administration's effort to single out aspects of the country's past that speak to different parts of American society. Past monuments have paid tribute to cultural hallmarks in African American, Native American, Asian American and Latino history.

The monument will be the ninth national park site that specifically commemorates women’s history. The only other national monument recognizing a female pioneer is the one Obama designated in 2013, the Harriet Tubman Underground Railroad National Monument in Maryland.

“Women’s history is America’s history,” Page Harrington, executive director for the Sewall-Belmont House and Museum, said in a statement.

Rhea Suh, president of the Natural Resources Defense Council, said the declaration not only "expands America's story" but "will protect this site from intrusive development and other harms in the future.”

The stately red-brick home, which now hosts receptions as well as panel discussions and other events, has served as a gathering place to lobby for women's political, cultural and economic rights. During its heyday, the party targeted lawmakers and presidents through a range of nonviolent means including marches, hunger strikes and speaking tours.

On Jan. 4, 1931, less than two years after the party moved in, Belmont declared, "May it stand for years and years to come, telling of the work that the women of the United States have accomplished; the example we have given foreign nations; and our determination that they shall be — as ourselves — free citizens, recognized as the equals of men.”

An effort has been underway since the early 1970s to protect the building, and the National Park Foundation announced that D.C. businessman David Rubenstein will contribute $1 million to support the site and its restoration needs.

Google also announced Monday that it is creating Expedition, a virtual tour of the monument, to enable schools across the country to view the historic landmark.