(California)
Natural Bridges State Beach is a 65-acre (26 ha) California state park in Santa Cruz, California, in the United States. The park features a natural bridge across a section of the beach and a eucalyptus grove provides habitat for monarch butterflies. During monarch butterfly migration, Monarch Butterfly Natural Preserve has up to 150,000 monarch butterflies from October through early February. (Ref: https://en.wikipedia.org/wiki/Natural_Bridges_State_Beach)