Conference participants should make the reservations themselves directly to the hotel.
Example places to stay, all in the city center, are:
De Gamlas Hem Hotel & Restaurant, Kirkkokatu 54: https://degamlashotel.fi/en/home/
Lapland Hotels Oulu, Kirkkokatu 3: https://www.laplandhotels.com/en/hotels-and-destinations/oulu/lapland-hotels-oulu
Nordic Art Hotel Lasaretti, Kasarmintie 13b: https://lasaretti.com/en/
Original Sokos Hotel Arina, Isokatu 25:https://www.sokoshotels.fi/en/hotels/oulu
Radisson Blu Oulu, Hallituskatu 1: https://www.radissonhotels.com/en-us/destination/finland/oulu
Scandic Oulu City, Saaristonkatu 4: https://www.scandichotels.com/hotels/finland/oulu/scandic-oulu-city
Scandic Oulu Station, Kajaaninkatu 17: https://www.scandichotels.com/hotels/finland/oulu/scandic-oulu-station