Click On Photos To See Our Menu! Johnstown's Heyday Diner is located in the heart of Downtown Johnstown, and features several momentos of Johnstown's rich history. They have affordable family home cooking for breakfast lunch and dinner, with daily specials. Order ahead from our take out menu, or dine in. There is a private area for small meetings and gatherings. Serving Johnstown, Richland Township, Westmont, Southmont, and all surrounding areas