HillCrest Urgent Care Dallas TX - Walk in Medical Clinic Dallas At HillCrest Urgent Care Dallas TX - Walk in Medical Clinic Dallas , you don’t need to worry about getting an appointment when you need one. Unlike most family practices, we are open 7 days a week and offer extended hours, easy online check-in, and walk-in appointments. While some physicians’ offices do not accept new patients, that is never the case at Hillcrest Medical.