But the open season is in any case very short, and the western straits are sometimes icebound during the entire year.
Coasts are icebound, and the W.
Are not uncommon, and the rivers are generally icebound for two and a half to three months - the Warta being under ice for 70 to 80 days, the Vistula at Warsaw for 80 days and (exceptionally) even for 116, and the Memel for 100 (exceptionally for 140).
The frosts are severe, the Danube being often icebound for three months.
The harbour is good, but generally icebound from December to May.