A while back I taught a workshop on the Wheel of the Year which is an agriculturally based model for living in communion with the cycles of the Sun, Moon, and seasons.

Living with and honoring these cycles for almost 3 decades has truly been one of the most beautiful practices for understanding my own cycles. It has helped me to alleviate much anxiety and be in flow with spirit.
If I had to pick one thing that has made the most positive impact on my life and spiritual path, this would be the One. (followed by meditation.)