A California fast-food institution celebrated its 70th birthday Monday, and what began as a tiny food stand in Baldwin Park has expanded to 334 locations in six states. KABC reported.

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In-N-Out opened its doors on Oct. 22, 1948. The hamburger chain is celebrating its anniversary by releasing its 2019 T-shirt in restaurants, and an official party will be held Nov. 17 in Pomona, the television station reported.

In-N-Out was founded by Harry and Esther Snyder, The Mercury News reported. Their descendants still own the chain, and current president Lynsi Snyder, 36, granddaughter of the founder, recently told Forbes she does not anticipate opening restaurants east of Texas, the newspaper reported.

In-N-Out was one of California's first drive-thru restaurants, the Mercury News reported. The newspaper said the world's first drive-thru restaurant was Red's Giant Hamburg in Springfield, Missouri, which opened in 1947.

A replica of the original In-N-Out stands near the first restaurant in Baldwin Park.