Diamond Bar/Walnut YMCA 22600 Sunset Crossing Rd Diamond Bar, CA 91765-1025 United States Phone +1 909-860-9622 Visit Website Join Donate Find More Ys Hours of Operation Mon - Sun: 12:00am - 12:00am Programs Camping and Outdoor Enrichment Before School, After School, and Early Learning Family Strengthening Health and Well-being Locate 34.0302585, -117.8197403