CORRECTION APPENDED: The caption said Zingerman's Deli celebrates its 25th anniversary March 16. The anniversary was March 15.

Entering Zingerman's for the first time has a tendency to be a bit overwhelming for some. It is difficult to find an inch of space in the 25-year-old deli that isn't covered with a vast selection of expensive meats and cheeses. A parton's view of the hanging menu listing dozens of sandwiches may be blocked by Zingerman's co-founder Ari Weinzweig. At 6 feet 4 inches tall, Weinzweig is a commanding presence.

Weinzweig can sometimes be found offering free samples of prosciutto, chatting with customers and instructing employees, but don't let him distract you from deciding between a #18 sandwich or a #20 sandwich (hint: the only difference is that one is grilled).

Weinzweig might be standing a bit taller today, as he and co-founder Paul Saginaw celebrate the deli's 25th anniversary.

In the quarter-century since Zingerman's opened its doors on Detroit Street in Kerrytown, the founders have expanded their business to include a bakery, creamery, sit-down restaurant, catering services and mail-order website.

It has developed a national following.

Ann Arbor resident Don Solomon said he has been a customer since opening day 25 years ago.

"No matter where I go in the country, when I say I'm from Ann Arbor, people ask me about Zingerman's," Solomon said. "Or they ask me to bring them a sandwich next time."

Saginaw and Weinzweig have refused offers to turn the deli into a chain.

"In 1994, they went against the opinions of their bankers and lawyers when they chose not to franchise," said Managing Partner Grace Singleton, who joined Zingerman's nearly five years ago. "They stuck to their core values and took the path less traveled."

On opening day in 1982, the Reuben sandwich cost $5 - or about $10.50 in today dollars. Now, the Reuben costs about $11.99. That is, except for today, when the deli will sell the sandwich for just $5, in honor of the price the year it opened.

It's not just the sandwiches that are expensive, either.

Earlier this month, a University Law School student group held its annual charity auction. One of the items for sale was the chance to have a Zingerman's sandwich temporarily named after the winner. The right to name a Zingerman's sandwich sold for nearly $700, despite the fact the name will only become permanent if sales of the new sandwich are successful.

On campus, the deli is somewhat polarizing.

"I find it hard to spend $12 on a sandwich, but I like them a lot," said LSA sophomore Angela Heuer, who attended the deli's 25th Anniversary street festival this past Sunday. "My boyfriend refuses to go there, though. He prefers going to Maize and Blue, which he says tastes better and costs five dollars less."

Some students feel so strongly about Zingerman's that they join Facebook.com groups with names like, "Zingerman's has the world's best food" or "Zingerman's deli is a ripoff.com." Others list Zingerman's as their religious views on the site.