Hosts and guests have been asking for a sauna filter for years. It seems Airbnb has simply dug in their heels and refused to do it. We've now got categories for "grand piano" and "caves" and just about everything else imaginable, but still nothing for saunas. Listed amenities include "hammock", "hot tub" and "pool"... but STILL no line for sauna. I offer a sauna and have had several guests tell me it's the reason why they booked. It's so frustrating that Airbnb won't listen to their hosts and guests and make this super simple upgrade.