First came H&R Block Inc. Then the downtown Kansas City, Mo.’s resurrection followed.

The development of a nine-block, $850 million entertainment district hinged on the nation’s largest tax preparer relocating its world headquarters 30 blocks north. The opening of its offices two years ago jump-started a redevelopment plan that city officials hope will reinvigorate a forgotten part of town.

“The tremendous downtown changes have given the residents a renewed sense of confidence and optimism about the future of the city,” said Bob Marcusse, president and chief executive of the Kansas City Area Development Council. “Externally, it’s really helped us to reset the image of Kansas City.”

Where most developers saw a downtown marred by parking lots and abandoned buildings, The Cordish Cos. saw an opportunity. The Baltimore-based company unveiled a plan to create the Kansas City Power & Light District, a vision that persuaded H&R Block to move.

“In order for us to go downtown and bring jobs into downtown, we wanted Cordish to push along with their plan under a specific timeframe,” said Greg Swetnam, a director at brokerage firm Kessigner Hunter who worked with H&R Block on its relocation. “We wanted an area that would attract the kind of employees H&R is looking for.”

The district is nearly complete. The first restaurants, Vinino Bistro and McFadden’s Sports Saloon, opened late last year and Cordish celebrated the grand opening in March. More retailers, restaurants and attractions will open through the year.

The area is anchored by the $275 million Sprint Center, a 24,000-seat arena developed as a public-private partnership between the city and AEG. The center opened in October and, so far, has hosted events including a Garth Brooks concert and the 2008 Big 12 Conference men’s college basketball tournament.

Still under construction, but also at the heart of the revitalization, is the $326 million Kauffman Center for the Performing Arts. The center will include a 1,600-seat concert hall and a 1,800-seat proscenium theater that will be home to Kansas City’s symphony, opera and ballet company.

A smaller theater, the Midland Theater, was recently renovated by the Anschutz Entertainment Group for $35 million. And the city recently overhauled the municipal auditorium to lure more Broadway plays there. “The Lion King” is starting in October and running for at least six weeks.

“Downtown is hot. Even people who have lived here and never go downtown keep rubbing their eyes and saying ‘wow,”‘ said Larry Larsen, a CB Richard Ellis Inc. broker in Kansas City.

Retail is slowly following the crowd. The district adds more than 450,000 square feet of retail space and about 60 percent of that has tenants who are open for business, Larsen said. It includes theme restaurants, event space, an AMC movie theater and retailers like GNC and Joseph A. Banks. Consentino’s Market will open its doors this fall, marking the first grocery store for the area in decades.

Residents already are warming to the downtown.

“People are back downtown with their pets, with their bikes and Vespas,” Larsen said. “Currently, we have an apartment shortage.”

About 16,000 people live downtown and that number is expected to grow to 24,000 by 2010, Larsen said.