It’s safe to assume Jon Jerde wasn’t thinking of people careening on zip lines beneath a canopy when he first envisioned the Fremont Street Experience, but it happened during his lifetime. The architect, who died Feb. 9, also lived long enough to see FSE on its way to its 20th year, at a time when Downtown Las Vegas’ casinos can boast two straight years of growth. It’s evolved from a concept designed to recapture some thunder from the booming early ’90s Strip into a 24-7 carnival with three concert stages, overhead Viva Vision shows dedicated to legendary rock acts and projected on a blocks-long screen, street performers, artists, assorted eccentrics, and the aforementioned zip lines.

Fremont Street added an experience after downtown casino owners joined together in the early ’90s to strategize a way to compete with newer Strip casinos such as The Mirage and Treasure Island. “They came up with the concept of working with the City of Las Vegas to close five blocks of Fremont Street to create this urban pedestrian mall that would connect the downtown hotel-casinos, and have an attraction that would be a draw to tourists to come down from the Strip,” said FSE’s director of marketing Thomas Bruny in a 2014 interview.

One idea was a Star Trek-inspired attraction based on the Starship Enterprise, which became Star Trek: The Experience at the Las Vegas Hilton. The Jerde Partnership envisioned a floating parade beneath a barrel-vault canopy supported by 16 massive columns. The risks presented by high winds led to a change in direction. At the suggestion of architect Mary Kozlowski, the underside of the canopy would become a four-block-long, 90-foot-wide LED display constructed of 2.1 million incandescent lights. On Sept. 7, 1994, Fremont Street became permanently closed to vehicular traffic and work continued until the grand opening took place on Dec. 14, 1995.

Jerde went on to design the Bellagio in 1998 before master planning The Palms and Wynn Las Vegas, but the Fremont Street Experience would continue to be refined. In 2004, Viva Vision received a $17 million overhaul that enabled current light-and-sound tributes to The Who and The Doors, as well as the new Imagine Dragons show Home in Vegas. Permanent stages were installed. In 2012, zip lines were added, and in 2014 Slotzilla was constructed to make flying over Fremont a permanent part of the atmosphere.

Some longtime locals lamented the loss of the Fremont that James Bond raced down in Diamonds Are Forever, but the 26,000-pound columns were there to stay. “What we’re doing down here is attracting roughly 15 million people a year, about 13 million visits from tourists on these four blocks under the canopy,” Bruny said in 2014. “We don’t think it would be attracting anywhere near that without the Fremont Street Experience.”

Fremont Street Experience, Viva Vision shows begin at dusk and runs every hour until midnight daily; Slotzilla, noon-midnight Sun.-Thurs., noon-2 a.m. Fri.-Sat., $20 for lower zipline. vegasexperience.com