Welcome to Katie Mullen’s, Denver’s largest Irish bar and restaurant located beside the Sheraton Hotel on 16th Street Mall. Find Us. Katie Mullen’s is a uniquely Irish Bar and Restaurant encompassing four bars and four themed experiences spanning over 11,500 sq feet. Katie Mullen’s brings an inventive yet traditional mix of Irish and American cuisine and prides itself on quality food, drink and customer service. With seating for over 550 people and showcasing the largest patio on 16th Street Mall, Katie Mullen’s Irish Restaurant and Bar provides the ideal setting for all occasions from business lunches to family celebrations to large corporate events.