Slice the peppers into rings, about 1/4 inch thick. You can rinse them well in a colander to remove most of the seeds if desired.
Combine vinegar, sugar, garlic, turmeric and celery seed in a large pot or dutch oven. Cook over high heat, whisking occasionally and bringing the mixture to a full rolling boil. Reduce to simmer, cooking 5 minutes.
Return mixture to a boil and add the sliced banana peppers. Bring to a full rolling boil and cook 4 minutes.
Pack into jars while hot – using a slotted spoon to fill sterilized canning jars.
Return the apple cider mixture to a rolling boil, cooking 6 minutes. Stirring occasionally so that it doesn’t boil over.
Remove from heat and carefully ladle brine over the banana peppers filling the jars, leaving about 1/4 inch of space at the top.
Stick a knife down into the jars to remove any air bubbles. Wipe rims and seal with lids. Top with 2 piece canning lids, do not over tighten.
Cool and refrigerate – or process in a hot water bath for 10 minutes if you want to shelf-stable preserve them.