Let KAYAK do the searching
Based on KAYAK hotel searches, the most popular destination is Rapid City (55% of total searches to South Dakota). The next most popular destinations are Sioux Falls (26%) and Deadwood (10%). Searches for hotels in Pierre (10%) are also popular.
KAYAK users have found double rooms in South Dakota for as cheap as $69 (Deadwood) in the last 3 days. The average price is $272.