Odránidir's Days, Months and Seasons

Days of the Week:
Sunday - Ulomwen
Monday - Ilenwen
Tuesday - Teiwen
Wednesday - Idinwen
Thursday - Thêlwen
Friday - Proswen
Saturday - Tircinwen

Months of the Year:
Gwenanrio (37 days) - Gwenanrio 1 is the first day of Ibilnas.
Yolrio (35 days)
Bûrrazrio (36 days) - Bûrrazrio 10 is the first day of Ulanas.
Ulomrio (37 days)
Lanweirio (37 days)
Remmethrio (36 days) - Remmethrio 3 is the first day of Tûmnas.
Eradrio (37 days)
Ayelrio (37 days) - Ayelrio 31 is the first day of Nothnas.
Nayelrio (36 days)
Navanrio (37 days)

Seasons:
Spring - Ibilnas (92 days)
Summer - Ulanas (93 days)
Autumn - Tûmnas (91 days)
Winter - Nothnas (89 days)

The year begins on the first day of Gwenanrio, which is also the first day of Ibilnas. The year ends on the last day of Navanrio, which is the end of Nothnas.