Difficulty:
Time-Consuming:

In a continued effort make the world of knitting a little sexier, I created these thigh high socks. They fit nicely on weights between approximately 56.5-63.5 kg (about 125-140 pounds), and are 71-72 cm long from the heel up (about 28.25 inches). I've also worked in an elastic, i-cord top to help the socks stay up on their own.
For this project, I used 2 skeins of Berroco Ultra Alpaca Fine wool (400m/100g skein, 1 skein per sock), four 3.75mm double-pointed needles, 1 stitch marker, 39.5-42 cm (15.5-16.5 inches) of 6mm elastic for each sock (you may wish to use slightly more or less, depending on how tight you want the top of the socks to fit), a sewing needle to sew the ends of the elastic, and a tapestry needle to close the i cord around the elastic. This pattern also makes use of my Lace #13 and Knit/Purl #3 stitch patterns (both adapted here to knit in the round).
Abbreviations Used in Pattern:
Sts = stitches.
SM = stitch marker.
K = knit (k4 = knit 4 stitches).
K = knit (k4 = knit 4 stitches).
P = purl (p4 = purl 4 stitches).
YO = Yarn over: bring yarn around needle so that it will be knit/purled as a new stitch on the next row.
K2tog = knit 2 stitches together. skpsso = slip one stitch, knit one stitch, then pass slip stitch over (with the left-hand needle, take the previously slipped stitch off the right needle and pull it over the stitch knit after it was passed).
P2tog = purl 2 stitches together.
K2rev = knit 2 stitches in reverse (ignore the first stitch, knit the second stitch, pulling it over the first stitch when done, then knit the second stitch)
P2rev = purl 2 stitches in reverse.
Knitting a Sock:
Top Band (i cord):
*Note: it is easier to knit around the elastic band than to try and insert it later.
Cast on 7 sts.
Work in i cord (see how-to video for "i cording" here) until there are 115 rows, and bind off.
Continue into Sock Body...
Pick up every stitch along the edge of the i cord (so, 115 sts), and begin knitting in the round.
Round 1: k16, k2tog, k15, k2tog, *k14, k2tog. Repeat from * to end of round.
Round 2: *k2rev, yo, skpsso, k2tog, yo, k2rev, knit 1. Repeat from * to end of round.
Round 3: knit.
Round 4: *k2rev, k2tog, yo, yo, skpsso, k2rev, knit 1. Repeat from * to end of round.
Round 5: knit.
Round 6: *k2rev, yo, skpsso, k2tog, yo, k2rev, knit 1. Repeat from * to end of round.
Round 7: knit.
(This 6-row repeat is essentially the main stitch pattern, and is continued throughout the sock until otherwise indicated (as in the heel and sole).
Making Decreases Through the Leg...
After the 6-row stitch pattern has been worked a total of 3 times, you will begin making decreases (which will cut into the stitch pattern repeat as you go) on the next round as follows:
k2tog, work 49 sts, skpsso, place SM, k2tog, work to last 2 sts, skpsso.
Make these 4 decreases every 12 rounds, 15 more times (so every 12 rounds, k2tog, work to 2 before SM, skpsso, slip marker, k2tog, work to last 2 sts, skpsso). After final decrease, 44 sts should remain in the round.
After final decrease, the stitches of the round will be divided into the top and bottom/sole sts of the sock. The first 21 sts should be divided onto one needle, and the remaining 23 sts onto another. The group of 21 sts will be worked into the heel, while the other 23 will be the top of the sock foot.
Working Heel Flap Only...
Knit the first 21 sts of the round, then turn work so that you will be working the purl side of those 21 sts.
Purlside: slip 1, (p2rev, p1)x6, p2rev. Turn work to face the front side of the 21 sts again.
Frontside: slip 1, k20, turn work.
*Note: this 2-row repeat now essentially is what will make up the second main stitch pattern of the sock for the heel and sole.
Repeat these 2 rows seven more times.
Shaping the Heel...
Next row of 21 sts (purlside): work 12 sts (adhering to heel/sole stitch pattern), p2tog, p1, ignoring the rest of the row, turn work.
frontside: slip 1, k4, skpsso, k1, turn.
purlside: slip 1, work 4, p2tog, p1, turn.
Repeat these two rows 4 more times, until 8 sts remain on the needle.
Start Rejoining the Round...
Next row (frontside): slip 1, k4, skpsso, k1. Continue the row by picking up and knitting 13 sts along the heel edge. Now continue by working the 23 sts making up the top of the sock foot (which will still be continuing the main stitch pattern). Be sure to keep these top sts on their own needle to avoid later confusion. Finish the round by picking up and knitting 13 sts along that end of the heel.
*Note: the 26 stitches total picked up on both sides of the heel will now be counted as part of the bottom sole/heel sts. So now the first 20 and last 13 of the round make up the bottom/sole of the sock, while the middle 23 stitches make up the top of the the sock foot.
Next round: (k1, k2rev)x6, k2. Work the top 23 sts, continuing the main stitch pattern. Work the remaining 13 (part-of-the-bottom) sts as k1, (k1, k2rev)x4.
Making More Decreases...
Next round: k18, skpsso. Work the 23 top sts. Work the remaining bottom/sole sts as: k2tog, k to end of round.
Next round: (k1, k2rev)x6, k1. Work the top 23 sts (still continuing main stitch pattern), work last bottom sts as: (k1, k2rev)x4.
Next round: k17, skpsso, work top 23 sts k2tog, k10.
Next round: (k1, k2rev)x6, work top 23 sts, (k2rev, k1)x3, k2rev.
Next round: k16, skpsso, work top 23 sts, k2tog, k9.
Next round: (k1, k2rev)x5, k2, work top 23 sts, k1, (k1, k2rev)x3.
Next round: k15, skpsso, work top 23 sts, k2tog, k8.
Next round: (k1, k2rev)x5, k1, work top 23 sts, (k1, k2rev)x3.
Next round: k14, skpsso. For top sts: k2tog, work 19, skpsso. For remaining sts in round: ktog, k7.
Next round: (k1, k2rev)x5, work top sts (now 21), (k2rev, k1)x2, k2rev.
Next round: k15, work top 21 sts, k8.
Next round: (k1, k2rev)x5, work top 21 sts, (k2rev, k1)x2, k2rev.
Next round: k13, skpsso. For top sts: k2tog, work 17, skpsso. For remaining sts in round: k2tog, k6.
Next round: (k1, k2rev)x4, k2, work top sts (now 19), k1, (k1, k2rev)x2.
Next round: k14, work top 19sts, k7.
Repeat the last 2 rounds 14 more times.
Shaping Toes...
Next round: (k1, k2rev)x4, k2, work top sts (now 19), k1, (k1, k2rev)x2.
Next round: k12, skpsso. For top sts: k2tog, work 15, skpsso. For remaining sts in round: k2tog, k5.
Next round: (k1, k2rev)x4, k1, work top sts now as: (k2rev, k1)x5, k2rev. Work remaining sts in round as (k1, k2rev)x2.
Next round: k11, skpsso. Top sts: k2tog, k13, skpsso. Remaining sts: k2tog, k4.
Next round: (k1, k2rev)x4. Top sts: k2, (k2rev, k1)x4, k1. Remaining sts: k2rev, k1, k2rev.
Next round: k10, skpsso. Top sts: k2tog, k11, skpsso. Remaining sts: k2tog, k3.
Next round: (k1, k2rev)x3, k2. Top sts: k1, (k2rev, k1)x4. Remaining sts: k2, k2rev.
Next round: k9, skpsso. Top sts: k2tog, k9, skpsso. Remaining sts: k2tog, k2.
Next round: (k1, k2rev)x3, k1. Top sts: (k2rev, k1)x3, k2rev. Remaining sts: k1, k2rev.
Next round: k8, skpsso. Top sts: k2tog, k7, skpsso. Remaining sts: k2tog, k1.
Last round: work all but the last 2 sts of the round.
Before binding off, ensure the top sts (now 9) and sole sts (now 11) are divided across two needles (top sts on one, sole/bottom sts on the other needle). Starting with the sole/bottom sts, alternate moving a stitch from each needle onto a third needle, so that the sts are all interlocking on the third needle, then bind off the sts two-at-a-time.
Finishing Up...
With a needle and thread, join and stitch the ends of the elastic band together. Then use a tapestry needle to stitch the ends of the i cord together around the elastic.