Let KAYAK do the searching
Based on KAYAK hotel searches, the most popular destination is Copenhagen (48% of total searches to Baltic Sea). The next most popular destinations are Riga (21%) and Stockholm (17%). Searches for hotels in Gdansk (14%) are also popular.
KAYAK users have found double rooms in Baltic Sea for as cheap as €12 (Tallinn) in the last 3 days. The average price is €127.