Thinking about the recent Halfling and Reptilian culture threads I had some ideas mashing the two together, and mixing them with some setting ideas I hadn't had time to use before.
The World
It's set on a low magic primeval world at the start of civilization, where only a few fledgling kingdoms exist, but most of the world is still a savage untamed land, where people must constantly fend against wild beasts and the elements. Technology exists, but it's still at its early stages, consisting largely of copper tools and crude engineering, with stone tools still used in many places. Bronze may have been discovered in some of the more advanced kingdoms but it's still not widely used.
Humans are not the only advanced species, but the races of the world are not magical creatures, like in traditional fantasy settings, but rather natural creatures that evolved to adapt to this particular world's circumstances. The "monsters" that characters face consist largely of the megafauna that permeates the world (including extinct creatures, like sabertooth and mammoths, as well as other creatures unique to this world), and the occasional magical creature that slips through the cracks from another reality. Mutated creatures might also be possibility, perhaps as the result eldritch energies or corrupting substances leftover from a prior era of a long forgotten past where magic may have been more powerful and prevalent, but ended in a major cataclysm that hurtled the world back into a primeval state.
The Jagged Cliffs
One of the regions of this world sports a large valley of jagged cliffs extending for hundreds of miles. The cliffs are large stoney protrusions extending across a vast expanse, like chunks of land rising hundreds of feet into the air then expanding away from each other leaving short stretches of land in between. Around some of these gaps of land hundreds of streams run through, some larger than others, sometimes merging into one another other, forming puddles and lakes stretching out onto the open regions beyond the cliffs, where the streams form into marshlands around the more fertile ground, growing deep green vegetation in contrast to the more arid soil of the stoney cliffs.
Races of the Jagged Cliff Region
Two races dominate this region: a race of large reptilian humanoids descended from lizards similar to crocodiles (Lizardmen), and diminutive mammalian humanoids closely related to humans (equivalent to Halflings).
The Halflings were the first race to settle this valley, almost a thousand years ago after they were driven out from a nearby region to the north by aggressive Beastmen that now dominate that region and frequently raid hapless travelers and human settlements. So the Halflings fled southeast till they found this valley and settled there, living in the trees around the marshlands and carving a simple primitive life, eating fish from the lakes and marshes, occasionally banding in large numbers to hunt large game, but largely unperturbed by the outside world.
But a group of Lizardmen migrated into the region several centuries ago, when a tribe from the coastal regions split off after a massive storm that scattered their numbers and left them wondering aimlessly until they found water rich land adequate to fit their needs. The carnivorous Lizardmen quickly settled the marshlands--neatly adapted to dominate the watery terrain--and the numerous Halflings became a staple diet for them, which the larger and physically powerful Lizardmen would hunt with frequency, making the marshlands uninhabitable for the little folk.
The Cliffhanger Villages
So the Halflings fled onto the jagged cliffs of the valley, climbing high--away from the reach of the predatory lizard folk, yet still reliant on the waters coursing below for sustenance. They became expert climbers, adept in rope use and cliffside construction, and settled the stoney cliffs, building Cliffhanger Villages that hung around the cliff's edge, ever watchful for lizard-sign below. Crude pulleys are used to lift food, water and materials to the sky-high homes, and this same system can be used to pull ground bound Halflings in the case of attack.
The Halflings also mastered the use of slings, javelins and darts, and the construction of crude traps, which they would use against the hordes of Lizardmem when the culling came, keeping the hungry lizards away from their lofty homes. They are ever watchful of trespassers into their land--ever wary of attack, given their bloodthirsty neighbors. Horns will sound the alarm if any approach, and the small nimble folk will rush through a network of hanging bridges and ropes that interconnect the villages from one cliff to another.