Update: Westbound Interstate 70 from Downtown Indianapolis to Interstate 465 reopened Friday. The work was finished two days early, clearing a main route for Gen Con attendees heading back to the airport from Downtown.

The interstate was expected to reopen by Monday morning.

Original: This weekend will bring more 65,000 attendees to the annual Gen Con event in Downtown Indianapolis.

People flying in for the event will want to be prepared for possible traffic hassles.

The main interstate connecting Downtown to the airport remains closed until after the convention concludes on Sunday. The closure of I-70 eastbound and westbound from the South Split (the intersection of I-70 and I-65 south of Downtown Indianapolis) to I-465 began Friday night, and the reopening is scheduled for 6 a.m. on Monday, Aug. 5.

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Indiana Department of Transportation spokeswoman Mallory Duncan said they have been in communication with Visit Indy, the Indianapolis International Airport and Gen Con, as well as other events and conventions coming to town, to disseminate information via social media and airport digital message boards.

Chris Gahl, senior vice president for Visit Indy, said the organization has been working with Gen Con over the last month to prepare attendees for the road construction. He said an estimated 25 percent of convention goers are arriving by air, and 75 percent will drive in for the event.

"We anticipate, and have been proactively sharing with Gen Con attendees, to expect an additional five to 15 minutes of travel time tied to these road improvements," he said. "While it’s not optimal timing, we feel confident the detours won’t impact Gen Con’s overall convention and the city’s visitors’ overall experience."

Duncan said weather pushed back construction projects and the I-70 closure needed to happen to stay on track.

"The 65 closure and 70 closure is in response to all the rain we got in May and June," Duncan said. "The south side needed to be done before we do a full closure of I-465 on the southeast side. It's just how the timing worked out, and we have a great detour in place."

She added that there won't be closures between the North and South splits this weekend in hopes of easing traffic.

INDOT worked with Google, Apple, Uber and Lyft to update their maps with closures so drivers can take appropriate detours. The agency has shared these detours:

Thru traffic: Take I-465 southbound, to I-65 northbound, then to I-70 eastbound.

From airport to downtown: Take I-70 eastbound to I-465 southbound and eastbound to I-65 northbound.

From downtown to airport: Take I-65 southbound to I-465 westbound and northbound to I-70 westbound.

Kellie Hwang is a reporter at IndyStar. Contact her at 317-444-6032 or kellie.hwang@indystar.com. Follow her on Twitter: @KellieHwang.