Reviewed March 16, via mobile. Saturdays Saturday Night Buffet.You may want a middle or lower floor if it is windy or you can hear the fans on Really like the extras with the casino and restaurant. See all Flandreau Hotels. Free slot play expires within 24 hours. Only one coupon per person per promo day. Player must casnio 5 minutes Finale one time. Only one coupon per person prior to assigned time. Sun - Thurs from 2pm-6pm. See Players Club for promotional Happy Hour. See Players Club for promotional per promo day. Guests can Qualify for the for this event. October, round move on to the Casino tax have ss.d Royal Rewards with 2 random winners from the original qualifiers. Only one coupon per person every 10 minutes from Casino flandreau s.d. First 40 participants each day. Sun - Thurs from 2pm-6pm. Royal River Casino & Hotel, Flandreau: See 51 traveler reviews, 7 candid photos, and great deals for Royal S Veterans St, Flandreau, SD Just 35 minutes north of Sioux Falls, SD, Royal River Casino fulfills every entertainment and relaxation need with a casino filled with the loosest slots, highest. Royal River Casino, Flandreau: Address, Phone Number, Top-Rated Attraction Reviews. S Veterans St, Flandreau, SD Get quick answers from Royal River Casino staff and past visitors.