Even though interest rates have chilled the housing market, there are still historic homes that sell as soon as they’re put up for sale, sometimes at irrational prices (like this one and this one — great houses, quick sales, wild prices). And, then, there are those that don’t. Here are six historic homes that have been listed for more than six months, all unsold.

In some cases, it’s easy to see why. Some of these are mansions — houses 4,000 square feet and up. They typically take longer to sell than more reasonably sized homes, although a few here and there sell quite quickly (especially in Winston-Salem). Sometimes price is an obvious reason, even in these days of $350 or $400 per square foot for bungalows. In other cases, it’s impossible to tell from the listings what the problem is. And with old houses, there’s no end to the possibilities.

Click on the links for more information about each house.