Nature is one of the greatest sources of happiness.
In fact, humans had lived in the lap of nature for millions of years and their stay in modern cities is comparably very very short. Still, now the majority of them live in close proximity to nature. In fact, we are very much dependent upon nature for its very survival (plants recycle carbon dioxide into oxygen; our food is a product of nature; and we can survive under a very limited range of variables of nature like temperature, etc.)
Nature is all free! It is there for everybody to stand and stare and derive happiness and solace from. It does not distinguish between rich and poor, strong and weak, man and woman.
It is free, not because it is cheap, but it is rather priceless.
When we see the moon, we see it in its entirety, no matter how many millions of people are seeing it at the same time. And similarly, the sky, the sun, the ocean, rain and sunshine, all are there for us to possess fully. Each can stare at the sky and claim all of it for his or her happiness.
Nature understands your moods. Slowly it lifts your spirits, makes you see your little woes, worries, and wounds in the right perspective of infinite time and space. You smile; you laugh, and you are happy again!
Yet do you realize that infinite beauty and happiness are lying around you in the form of nature?
Do you appreciate this fact and draw happiness out of it?