'Circle M' opened in 1975 in Wantagh.
Nikolas Tsotsos and his older brother John came from Sparta, Greece, and figured they'd only stay a few years.
Now, 50 years later, they're celebrating their anniversary with a $5 menu for their customers.
Loyal customers lined up to wait outside in the rain to support their favorite diner.
The most popular item on the menu is the Mykonos salad with house dressing that's been on the menu for more than a quarter of a century.
The customers say the best part about the diner is the generations of memories.
"Back in the day when they had dances and everything we used to come here," Helen Mchale said.
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