On the south side of the Oklahoma City National Memorial & Museum, just above the tree line, a brand-new, 40-foot bay window overlooks a sprawling outdoor memorial. The Survivor Tree, an American elm that endured the tragic events of April 19, 1995, stands as a symbol of resilience; the grassy field of empty chairs, as rows of remembrance. And rising above it all is the ever-changing skyline of a city that, in the face of unspeakable heartbreak, committed to its recovery and continues to reinvent itself.

Two decades have passed since Oklahoma City’s darkest hour. Ask anyone who was around then, and they’ll share the same head-shaking sentiment: It’s hard to believe it’s been 20 years. But in that time, the people of Oklahoma City have refused to let the tragedy define them. Through a series of public and private investments, they’re revitalizing their once destitute downtown. And by pledging to honor the victims of the Alfred P. Murrah Federal Building bombing, they’re educating a new generation and sharing the remarkable stories of hope that changed their city forever.

In December 1993, nearly 16 months before the tragedy, Oklahoma City passed a temporary sales tax to fund an ambitious redevelopment program known as Metropolitan Area Projects, or MAPS. The $365 million initiative included renovations to the convention center, music hall, and fairgrounds; construction of a ballpark, arena, canal, and library; and development of a trolley system.

After the events of April 19, 1995, there were two schools of thought. “One was we needed to back off this MAPS deal and focus on the recovery efforts,” says Mike Carrier, president of the Oklahoma City Convention and Visitors Bureau. “The second was that we could recover and rebuild, and we could move this city forward with MAPS all at the same time.”

The latter won out.

In 1998, after years of planning and construction, the first project under MAPS was completed: a 12,000-seat ballpark in the heart of the Bricktown district that’s now home to the Oklahoma City Dodgers, the Triple-A affiliate of the Los Angeles Dodgers. When the park opened, there was a collective “ah-ha” moment, Carrier says.

“Concern was mounting because people weren’t seeing a lot of activity initially, but that’s the nature of these types of publicly funded projects,” he says. “When that beautiful ballpark opened, though, everybody thought it was phenomenal. It really set in motion the rest of the major projects over the next several years.”

Those projects included the construction of a riverfront and a series of locks and dams along a 7-mile stretch of the North Canadian River. Once nothing more than an eyesore running through the city, this section of the waterway—renamed the Oklahoma River—is now a mecca for competitive water sports and family recreation. The Boathouse District along the river is the official U.S. Olympic and Paralympic training site for rowing, canoeing, and kayaking, and it hosts a number of elite regattas annually. Not an Olympic-caliber athlete? The district also offers dragon boating, paddleboarding, zip-lining, and more.

The Chesapeake Energy Arena (known as the Ford Center when it was completed in 2002) has been home to the NBA’s Thunder since 2008, and fans have embraced their team from virtually the opening tip: In its second season, the Thunder sold out of season tickets and ranked 12th out of 30 teams in total attendance despite playing in one of the league’s smallest markets.

With each successive project, Carrier says, the dominoes started to fall. “Suddenly, downtown began to have life after 5 o’clock, and that spurred interest in living there.” In fact, recent census data shows that Oklahoma City is one of the most popular areas in the country for millennials to call home.

Private development dollars also started to flow—to the tune of about $5 billion—in the form of retail, restaurants, and residential projects, Carrier says. Corporate headquarters began popping up in downtown. The $750 million Devon Energy high-rise building—an anchor in the city’s skyline—was completed in 2012, as was the $100 million renovation of SandRidge Energy’s campus.

Bricktown, the former warehouse and distribution district that decades of decline had left all but vacant, is now positioned as the premier entertainment district in the city thanks to the new ballpark, a tree-lined canal filled with water taxis, and more than 45 bars, restaurants, retail outlets, galleries, and museums.

“The city’s attitude from the beginning was ‘We’re going to make Oklahoma City a better place to live, work, and play,’” Carrier says. “Tourism was a byproduct of that. When Bricktown and other areas began to flourish, suddenly there was a reason for people to come to here. As a result of the improvements over the past 20 years, we now have a very diverse and prosperous tourism industry.”

One of the city’s main draws is the Oklahoma City National Memorial & Museum. Occupying part of the former Journal Record Building, the museum sits adjacent to the 3.3-acre outdoor memorial where the Murrah Building once stood.

In addition to marking the 20th anniversary, 2015 brings with it the completion of a yearlong, $10 million renovation project at the museum that unveils never-before-seen evidence, interactive exhibits, and facility upgrades—including the stunning glass overlook.

“We’re very excited to have basically opened a new museum,” says executive director Kari Watkins. “The story is the same, but how we tell it is vastly different.”

The story has always been told by way of panels, artifacts, and videos. But new interactive features throughout the museum give guests—particularly young ones—a chance to dive deeper into the investigation, follow the trail of evidence, and most importantly learn about the city’s response.

Making an event from two decades ago meaningful to today’s audience was a primary focus for those who undertook the renovation. New technology features like a mobile app, 55-inch touch screens, and an exhibit called the Responsibility Theater provide a more hands-on experience and create opportunities for young people to think critically about certain issues—perhaps in ways they’ve never been pushed before.

“We’ve made the site relevant for people who don’t know the story, and those who are familiar with it are able to engage in it again because of all the new evidentiary material that wasn’t here two years ago,” Watkins says. “We’re very pleased with the progress the museum has made. We’re teaching a new generation, which is key. If we don’t tell them, the story will be lost.”

Among the lasting memories from that day was the touching response. “Out of tragedy came courage, and we’re trying to educate people about what visiting rescue workers and journalists called the ‘Oklahoma Standard’: A community-wide display of spontaneous help and generosity in the aftermath of the bombing,” Watkins says.

To commemorate the 20th anniversary, Oklahomans are asked to recommit to the Oklahoma Standard this month by performing one act of service, honor, and kindness in a spirit of giving that has spread well beyond the boundaries of Oklahoma City.

Corporations like Ambassador Hotel Collection, which has one property in Tulsa (Ambassador Hotel Tulsa) and two in OKC (Colcord Hotel and Ambassador Hotel Oklahoma City), are participating in the initiative. The luxury boutique hotel group is giving its employees up to four hours of paid time off in order to complete an act of service. Jennifer Burgess, corporate director of e-commerce and marketing, says all associates have been educated about the program, and the hotel group plans to share its employees’ experiences via social media and internal communications throughout the month.

About an hour to the northeast, in Stillwater, Oklahoma, the OSU Foundation just completed the most successful fundraising campaign in state history, called Branding Success. The seven-year, more than $1 billion endeavor will provide funds for scholarships, endowed professorships, advanced facilities, and innovative academic programs—a generous display of giving back while looking forward.

Oklahoma City continues to reinvent itself. Tax collections are underway as part of another MAPS initiative: MAPS 3. This latest program funds eight projects and will raise an estimated $777 million through December 2017. Construction has already begun on a number of these upgrades.

A new cross-town boulevard is in the works, as well as a 40-acre downtown park and more residential developments. Carrier says the city has already started developing a state-of-the-art whitewater rafting and kayaking center in the Boathouse District, and it will begin installing a modern streetcar system later this year.

“Everywhere you go in the city, new things are happening,” Carrier says. “There’s new energy and new life coming back to downtown every day, and people will continue to see growth in our downtown area. It’s a special time to visit.”