Ever hear the joke about what’s on the other side of Worcester? No one knows, the map just says “here there be dragons.”

With apologies to Western Massachusetts, which is a lovely place and as far as we know not overrun with dragons, they’ve now got a comeback: what’s on the other side of Worcester? Affordable condos, but not for long.

With September’s sales in the books, The Warren Group’s analytics team looked at the condominium market for the first three quarters of the year. Two weeks ago they looked at single-family sales closed through August, and the condo market doesn’t follow quite the same pattern of higher prices, lower number of sales.

Towns in the western part of the state have had a great year so far for median condo price increases year over year; North Adams, Great Barrington and Dalton are the top three with increases of 198 percent, 180 percent and 134 percent, respectively. Lee and Lenox are also in the top 10, and Berkshire County had the highest increase in median price of all the counties at 39 percent.

Communities south of Boston were the big winners in terms of an increase in number of condos sold. Seven of the top 10 were in Plymouth County: Whitman (220 percent); Abington (178 percent); Pembroke (129 percent); Marshfield (125 percent); Brockton (124 percent); Wareham (113 percent) and Hanson (107 percent). Plymouth County as a whole had the largest increase in number of condos sold, at 93 percent.

All figures here are for condominiums sold year to date through September for both 2016 and 2017; towns with fewer than four sales in either year were excluded, for a total of 244 communities.

A few towns did align more closely along the expected higher prices, fewer sales. Leicester is clearly suffering from the inventory shortage shared by the rest of the state; number seven in median sale price percentage increase, it is dead last in percentage of sales, down 61 percent. On the other hand, Osterville ranked number seven in price increase and came it at number 14 for increase in number of sales. Wareham and Hamilton were both in the top 10 for number of sales and near the bottom for price increases.

Among the counties, Berkshire had the largest increase in median price from $158,000 to $219,000; Barnstable lost the most value, if it can be termed that, with a 1.7 percent drop equating to a drop of $4,500. Plymouth increased its number of sales an astonishing 93 percent, from 528 at this time last year to 1,020 this year. Nantucket dropped 27 percent, from 29 to 20.

The state overall saw a 3.2 percent increase in the number of condos sold and, coincidentally, the same percentage increase in the median price, from $330,000 to $340,500.

So even if Western Mass is overrun with dragons, you may want to snap up a condo near the New York border while you can still afford it.