A childhood belief about places

For a long time I puzzled over why Michigan City, Indiana is so named, being in Indiana and not Michigan. Then one day, looking at a map, I felt kind of stupid, noticing the obvious answer, namely that it is on the shore of Lake Michigan. Soon afterwards I began to discover that there are other cities named for the great lake on whose shore they are located, like Erie, Pennsylvania and Superior, Wisconsin. Then one day, I was perplexed, discovering Huron, South Dakota on a map, quite far from Lake Huron. I asked my sister why it was named that, so far from the great lake by the same name. My sister told me that Lake Huron was once much bigger than it is now and that back then it extended all the way to Huron, South Dakota. As far fetched as that seemed, I believed it for a long time. The day I fanally began to doubt such an explanation was the day I discovered Ontario, California on a map.