Slice vegetables and arrange them in a bowl. Sprinkle with salt and mix well, so the salt gets to all vegetables slices. Set aside.
Add vinegar, sugar, celery flakes and red pepper flakes to a saucepan and bring to a boil. Cook stirring until the sugar dissolves. Remove from the heat and add ice cubes to the pan.
Transfer salted vegetable slices into a ball wide mouth jar (2 quarts) and pour with the prepared mixture. Pack sliced vegetables loose enough, so the spiced vinegar mixture can reach to all slices.
Seal jars with the lids and place in the fridge for at least 2 hours before using. May be stored in refrigerator up to 2 weeks.