The Hartford Quilt Block (sometimes called the Hope of Hartford or the Hope from Hartford Quilt Block) is basically 4 y-units coupled with a side rectangle, revolving around a central square. In some ways the design is similar to the Air Castle Quilt Block and the Friendship Star Quilt Block, as all three of these designs are variations on a theme: Half Square Triangles revolving around a central square unit.
The Hartford Quilt Block is based on a 5x5 grid but is what we call a "half drop" pattern, meaning that the units don’t line up in straight rows and columns. Instead, they are staggered over one column in the grid. This makes the design very interesting visually. However, the 5x5 grid, coupled with the use of HSTs and QSTs makes this a more difficult block to calculate for rotary cutting. The cut sizes for 5", 10" and 15" finished blocks work out evenly, but other size blocks require measurements that must be rounded to the nearest eighth, so the measurements do not work out neatly in sizes that are not multiples of 5. The bottom line is that you need to be really precise when sewing and cutting those "off" sizes.
In order to make this block, you will need to know how to sew partial seams. If you don’t know how (or can’t remember how) here is a quick tutorial.