The Oslo Hat is worked in two strands of yarn held together from the bottom up in stockinette stitch. The first part of the hat is worked on a 40 cm [16 inches] circular needle, while the top of the hat is worked either on double-pointed needles or on a circular needle using the Magic Loop technique.
Begin by working a swatch to check that you have the correct gauge.
Sizes: XS (S) M (L) the approx. equivalent to baby (junior/woman) woman (man)
Measurements: Fits head circumference 47-50 (50-55) 55-59 (59-62) cm [18½-19¾ (19¾-21¾) 21¾-23¼ (23¼-24½) inches]
Gauge: 22-23 sts x 32 rows = 10 x 10 cm [4 x 4 inches] in stockinette stitch on 3.5 mm [US4] needles
Needles: Circular needles: 3.5 mm [US4] / 40 cm [16 inches]
Double-pointed needles: 3.5 mm [US4]
Materials: 100 (150) 150 (150) g Arwetta Classic by Filcolana (50 g = 210 m [230 yds])
or Sunday by Sandnes Garn (50 g = 235 m [257 yds]).
Note that two strands of yarn are held together throughout, and that the yardage given is the total yardage needed.
The dark blue Oslo Hat in the picture is knitted in two strands of Sunday in the color Sailor in the dark from Sandnes Garn.
The dark brown Oslo Hat in the picture is knitted in two stands of Arwetta (Red squirrel) from Filcolana.
The light brown Oslo Hat in the picture is knitted in two strands of Sunday in the color Croissant from Sandnes Garn.