Crossroads Medical Center. 400 Corporate Center Drive, Vandalia, OH • Phone: (937) 454-5296 Map and directions • Access your on-line Patient Portal. Office hours: Monday 7:30 am - 5:00 pm • Tuesday 7:30 am - 5:00 pm • Wednesday 7:30 am - 5:00 pm • Thursday 7:30 am - 5:00 pm • Friday 7:30 am - 3:00 pm If you need to reach your provider after our office is closed, please call (937 ....