Loading view. There are no upcoming events. There are no upcoming events. Mariandale Retreat & Conference Center Events Venues Mariandale Retreat & Conference Center 299 North Highland Avenue Ossining, NY 10562 United States Get Directions 914-941-4455 x119 Events at this venue Today Upcoming Upcoming Select date. Previous Events Today Next Events Subscribe to calendar Google Calendar iCalendar Outlook 365 Outlook Live Export .ics file Export Outlook .ics file