What a great question -- and not as easy to answer as I first thought. There are other iconic steakhouses in town that you might think are as old as the Frontier Steakhouse, but they aren't. The Plaza III, for example, opened in 1963. And then there's the original Hereford House at 20th and Main, which was already three years old when the Frontier opened and might be around today if some mean ol' arsonist hadn't torched the joint a couple of years ago.
The Frontier Steakhouse -- a family-owned steak-and-spud restaurant in Kansas City, Kansas -- celebrated its 50th birthday this year. When the Laffoon family opened the restaurant, the following dining spots were already in business: the Savoy Grill -- the oldest continuously operating restaurant in Kansas City -- along with the original Stroud's, the original Jasper's on 75th Street, and the first Peanut Bar & Grill on Main Street. And on a somewhat less glamorous note: Mugs Up Root Beer Drive-In in Independence.
The other long-lasting restaurants that come to mind? Cascone's Grill in the City Market (yeah, it's moved locations several times in its long history), and the venerable Cascone's Italian Restaurant on North Oak Trafficway. El Torreon Mexican Restaurant in Overland Park opened in 1960 and is still in business.
Anyone recall any others?