Might be easier if you see the mileage between checkpoints:

FAIRBANKS
60 miles
MANLEY HOT SPRINGS
90 miles
TANANA
66 miles
RUBY
119 miles
GALENA
50 miles
HUSLIA - 1/2 way
82 miles
KOYUKYUK
86 miles
NULATO
22 miles
KALTAG
47 miles
UNALAKLEET
85 miles
SHAKTOOLIK
40 miles
KOYUK
50 miles
ELIM
48 miles
GOLOVIN
28 miles
WHITE MOUNTAIN
18 miles
SAFETY
22 miles
NOME