The Ryder Cup - golf’s premier international tournament - opens northwest of Chicago today.

Organizers estimate 240,000 people will attend the tournament to watch the world’s best golfers face off.

Teams from around the world will compete all week at Medinah Country Club.

Ed Stevenson runs two neighboring golf courses in DuPage County. He said the area is used to having major PGA events hosted at Medinah, but the Ryder Cup is an even bigger deal.

“In some ways this is more like having a mini-Olympics than it is even having a major golf championship,” Stevenson said. “Particularly for those of us in the golf business, it’s incredibly exciting.”

Jerry DeMarco owns an Italian restaurant near the Ryder Cup course. He said the tournament is good for business.

“We’ve been here 20 years,” DeMarco said. “We were here for the [1999] PGA and our business tripled. Ryder Cup is bigger than the PGA. I think it’s going to be four times greater.”

DuPage County estimates Ryder Cup will bring in about $70 million in tax revenue and hotel and restaurant business.

The US only hosts the Ryder Cup every four years.

Lake Park High School, about an hour northwest of Chicago, neighbors the Ryder Cup golf course.

The tournament means high school classes are cancelled for the whole week.

Jennifer Jungel is communications manager for the school district. She said Ryder Cup officials and the district came to an agreement about a year ago on how to manage the week of the tournament.

“The Board of Ed chose to close school for this week,” Jungel said. “Medinah Road right in front of our school is closed and so there is no public access to our buildings at all this week.”

Jungle says the district will be paid about $415,000 for leasing its facilities to Ryder Cup and providing hundreds of volunteers.

The money will go toward a new turf football field.

The Ryder Cup continues through Sunday.