There are also options to traditional "trick or treating" that allow your children to celebrate in a controlled and safe environment. The Arcadia Public Library is offering a trick or treat in the library for Arcadia residents, TODAY, Wednesday, October 26th at 4:00 pm and 6:30 pm. Call the library for information and registration at (626) 821-5567. The City will be hosting their annual Halloween event at the Community Center on Halloween, Monday, October 31st from 4:30-6:30 pm. The Community Center event is open to the public.