The future of Walt Disney World can be glimpsed in one of the resort's oldest rides.

By the end of the month, Disney plans to debut a redesigned queue for the Haunted Mansion, the classic dark ride that is one of the Magic Kingdom's original attractions. After 40 years of slowly shuffling toward the attraction's entrance, waiting riders will instead be able to move through an expanded graveyard filled with elaborate crypts — such as the tomb of a composer where instruments carved in the stone play music when touched.

It is the newest in a growing roster of "interactive queues" Disney is designing for some of its most popular rides as the giant resort attempts to better address that age-old theme-park problem: long lines.

During the past four years, Disney has added interactive elements to the lines for several other attractions, including Space Mountain and The Many Adventures of Winnie the Pooh in the Magic Kingdom, and Soarin' in Epcot. More are in development.

The Haunted Mansion queue also provides an early window into the kind of work now under way as part of Disney's "Next Generation Experience" project, a broad initiative aimed at using new technologies to make its increasingly busy theme parks easier and more enjoyable to navigate.

Disney has budgeted $1 billion for the project — enough to build a half-dozen or more marquee rides — which is being driven in part to make sure that swelling crowds don't ultimately choke the parks, spoiling visitors' vacations and deterring repeat visits.

Improving the waits outside popular rides is just one aspect of "NextGen." Another component includes a reservations system that would let guests book ride times from home and bypass the lines entirely.

"This is a really major project. And I think [it] would be viewed by everybody in the parks as probably the most significant thing we can do in the years ahead," Walt Disney Co. Chairman John Pepper said this week during Disney's annual shareholders' meeting in Salt Lake City. A shareholder had just asked Disney's senior leadership about its plans to develop more queues such as the Haunted Mansion's.

"It's costing a lot of money," Pepper added, "but it's going to be worth it, we think."

Disney has always paid particular attention to its ride queues, designing lavishly themed, detailed waiting lines that serve as "pre-shows" to help establish an attraction's story line. Queues alone can consume 10 percent to 20 percent of a Disney attraction's overall capital budget.

But complaints about long waits have remained a thorn in Disney's side. Line length consistently "falls either at the top or very near the top" of issues cited by guests in Disney's voluminous customer-satisfaction surveys, said Lori Georganna, vice president of research for Walt Disney Parks and Resorts.

"When we talk to them about it, they just want to get to the fun faster," Georganna said.

That's a key phrase now driving Disney's narrower effort to develop more interactive queues and the broader NextGen initiative.

The first attraction to be retrofitted with an interactive queue was Soarin', the popular glider-simulator ride in Epcot where wait times routinely exceed an hour. In 2007, Disney installed giant video screens in the queue, equipped with motion-detection equipment and heat sensors that allow big groups of guests to play collaborative video games while they wait in line.

Disney said it conducted what it calls a "pre-post" survey tied to the project, in which park researchers asked guests — before the games were installed and after — what they thought was a reasonable amount of time to wait for the attraction.

"Guests were willing to wait 12 percent longer because of the interactive experience," Georganna said, equivalent to an extra seven minutes or so during an hourlong wait.

The resort has extended the approach to more attractions. In 2009, it added 87 video-game stations to the queue for Space Mountain. And in November, Disney unveiled a far more elaborate example at the Many Adventures of Winnie the Pooh in the Magic Kingdom. That line now features a play area for young children, with a gopher-filled vegetable garden and oversized touch screens of virtual dripping honey that can be wiped away to reveal characters underneath.

Disney Parks Chairman Tom Staggs cited the Pooh queue as an example when he laid out some NextGen details during an investor conference last month.

The Haunted Mansion queue is arguably even more intricate.