Let KAYAK do the searching
Based on KAYAK hotel searches, the most popular destination is Copenhagen (54% of total searches to Baltic Sea). The next most popular destinations are Stockholm (28%) and Helsinki (10%). Searches for hotels in Ystad (8%) are also popular.
KAYAK users have found double rooms in Baltic Sea for as cheap as $14 (Riga) in the last 3 days. The average price is $172.