You're lucky to have had the experience of an engaged parent and an eternal environment into which your mind could flower. I grew up on the border between city and country, school and work in the former and liberty in the latter. I'm fairly sure that's why I favour solitude in nature when I need to compose myself and return to my own pace.
A lot of my childhood was spent in wandering rocky seashores, every pool an ocean filled with mysterious life, or crouched by streams which seemed to my tiny eyes the size of rivers, populated by behemoth tadpoles and intricate superstructures of water striders. I remember the microscopic as being much larger in my childhood, perhaps due to better eyes or a mind less bound up in the world of names and form the better to appreciate William James' buzzing blooming confusion.
These days when I want to sink into the same contemplative trance of wonder, nothing beats the dizzying fathoms of the night sky. In the same way that contemplating vast tracts of time manifest awe in my understanding of space, so enormity illuminates eternity. That's natural, I suppose, since Einstein cleaved them together.
It starts in solitude, perhaps as once long ago on a beach in Australia, near Cairns on the Northwestern coast, alongside the Barrier reef. Walking a mile down the sand, the surf hissing on one side, on the other the tree line electric with the sound of cicadas and writhing with cane toads. Here, far from the meagre pools of electric lighting in the three street town one leaves behind, one looks up into the jewelled sky, the obsidian dome shot with distant glimmering camp fires, Nuit's ochre hair catching the light at sunset; words are just grimy windows into our minds' inability to express it; one looks up into that - and there arises a creeping sensation of majesty, increasing vertiginous profundity, a skin-crawling almost sexually-intellectual arousal-awareness of the vastness, the mystery, the sacred. Exactly as you say, we hang between eternity and infinity, the macroscopic and microscopic, sometimes nothing, sometimes everything.