Let KAYAK do the searching
Based on KAYAK hotel searches, the most popular destination is Porto (92% of total searches to Douro). The next most popular destinations are Vila Nova de Gaia (3%) and Foz Tua (3%). Searches for hotels in Mesao Frio (2%) are also popular.
KAYAK users have found double rooms in Douro for as cheap as $26 (Viseu) in the last 3 days. The average price is $195.