Final preps were underway and thousands were already checking in Wednesday as the 2015 Seventh-day Adventist Convention draws church members from around the world

One of those is Upendo Mewana, originally from Tanzania.

“I've met up with people we used to live together in Kenya,” Mewana said.

Mewana arrived early to explore San Antonio.

“We've been here for about two or three days. We've walked around. It feels great,” Mewana said.

The Convention and Visitors Bureau says this conference is a game changer.

“It does show San Antonio can accommodate in a very successful way this size of a conference,” Casandra Matej with the San Antonio Convention and Visitors Bureau said.

Nearly 70,000 are expected to attend the convention bringing an economic impact of more than $40 million to the city.

“People will be staying at our hotels. They'll be enjoying our restaurants, our attractions,” Matej said.

That means big bucks for the city and businesses. And many restaurants are catering to the crowds.

Casa Rio is one restaurant debuting a special menu, specifically designed for Adventists' vegetarian diets.

“They are all about healthy living,” Elizabeth Lyons with Casa Rio said.

Happy hour is changing too.

“A new watermelon agua fresca. Non-alcoholic. No caffeine. All natural made fresh every day here in our kitchen,” Lyons said.

The restaurant is also offering food vouchers that can be purchased early in the week because Adventists don't spend money on their Sabbath.

Convention officials say all of this sends a big message to future partners: San Antonio can handle anything that comes its way.

The conference began Wednesday. It will take place at the Convention Center and Alamodome, so be prepared for an extra busy downtown over the next 10 days.