After a few very l-o-n-g drives on this trip, it was nice to have a shorter one--less than two-and-a-half hours of driving time from our Serengeti Lodge to the Ngorongoro Serena Lodge, with stops on the way at the Maasai Village and Oldupai Gorge.
The countryside was dotted with traditional round, thatch-roofed African homes. In contrast to the Maasai villages, these hamlets looked downright modern:

The Ngorongoro Conservation Area (NCA) is over 3,000 square miles of protected land bordering the Serengeti. Two hundred years ago, the Maasai moved in, and approximately 42,000 still live there, most of them herders of cattle, goats, sheep, and donkeys.
The most famous feature of the NCA is the enormous Ngorongoro Crater, the world's largest intact volcanic caldera. The almost vertical walls are 2,000 feet tall, and the flat, almost perfectly circular crater floor covers 102 square miles. The original volcano, which erupted and collapsed two or three million years ago, could have been as tall as 19,000 feet--the size of Mt. Kilimanjaro. These days Ngorongoro Crater basks in the glory of being a UNESCO World Heritage Site and is listed in some places as one of
the Seven Natural Wonders of Africa.
The local Maasai are allowed to graze and water their herds in the crater, but they may not live or grow crops there. In fact, they have to actually leave the crater at night.
Being in the crater is like being a microscopic amoeba in a petri dish; the surface is flat, the sides rise perpendicular to the floor, and the ground is teeming with life:
During our morning drive, whipped cream clouds sat ponderously on the caldera rim:
Later in the day, the clouds lifted, and we could see the smooth rim top, unchanging for almost the full 360 degree view.
With approximately 30,000 large animals, the crater has the highest density of big game in all of Africa, which is why it is called Africa's Garden of Eden. If there is a snake in this garden, we didn't see it during our day-long drive, but we saw just about every animal we had seen in other places, with the exception of topis, impalas, crocodiles, and giraffes, which for various reasons don't inhabit the crater.
I kept a list of what we saw, and it's pretty impressive:
wildebeests
water buffaloes
warthogs
lions
zebras
flamingos
*crowned cranes
ostriches
warthogs
brown plover
hippos
hyenas
elephants
hartebeests
jackals
Kori bustard
white-backed vulture
spur-winged goose
hyrax
*Hildebrandt's starling
butterflies
yellow-billed kite
Speke's weaverbirds
sacred ibis
Grant's gazelles
Thomson's gazelles
vervet monkeys
*
Only sighting on our trip