Drain cherries well, and finely chop. Press gently between paper towels to absorb excess moisture; set aside.
Beat butter at medium speed with an electric mixer until creamy. Gradually add sugar, beating until light and fluffy. Add eggs, 1 at a time, beating just until the yellow yolk disappears.
Sift together flour, salt, and baking soda; stir in chopped cherries. Add flour mixture to butter mixture alternately with sour cream, beginning and ending with flour mixture. Beat batter at low speed just until blended after each addition. Stir in vanilla. Pour batter into a greased and floured 9- x 5-inch loaf pan.
Bake at 325° for 1 hour or until a long wooden pick inserted in center of cake comes out clean. Cool in pan on a wire rack 10 minutes. Remove from pan; cool completely on wire rack.