More like The Tomorrow Windows

anchored on:science fictioncontemporarytime traveladventurousmysterious

but

Narrow

ChockySeries
series2 books1968
Science fiction, mysterious in tone, about aliens, set in contemporary.
“The BBC produced a radio adaption by John Tydeman in 1967.”
from the catalogue
Start with Chocky →
CavorSeries
series2 books1901
About space exploration, set in the moon and early 20th century.
“H. G. Wells's 1901 novel The First Men in the Moon is narrated by the businessman Bedford, who joins the reclusive scientist Cavor after Cavor invents cavorite, a gravity-blocking substance that carries the two men to the Moon.”
from the catalogue
Start with The First Men in the Moon →
Time Travelers Never DieSeries
series2 books1996
Set in our world.
Start with Time Travelers Never Die →
The Stonehenge GateNovel
Jack Williamsonstandalone novel2005
Adventure, about expeditions and space exploration, set in africa.
“Stumbling on ancient stones in the Sahara Desert, four adventurous excavators and poker buddies realize that they have discovered a gateway to other worlds, from technologically advanced planets to primitive civilizations.”
from the catalogue
Thrice Upon a TimeNovel
James P. Hoganstandalone novel1980
Hard science fiction, about identity.
“Amazon: When Murdoch was summoned to his grandfather's isolated Scottish castle, he had no idea of the old man's latest discovery -- nor where it would lead him.”
from the catalogue
A Tale of Time CityNovel
Diana Wynne Jonesstandalone novel1987
About quests and coming of age, set in otherworld and early 20th century.
“In 1939 an eleven-year-old London girl is kidnapped to Time City, a place existing outside the stream of time and manipulating the history of humanity, where she finds the inhabitants facing their worst hour of crisis.”
from the catalogue