1 cup diced celery
1 cup diced cored, peeled apples
1/2 cup coarsely chopped walnuts
1/2 cup seedless red grapes, halved, optional
1/2 to 3/4 cup mayonnaise
Combine celery, apples, walnuts, and grapes in a medium bowl.
Stir in mayonnaise.
Serve at room temperature or chilled.