I was fortunate enough to catch an article on Gnome Stew this week entitled Quick and Dirty Overland Encounter List Template, which referenced another article entitled Quick and Dirty Location Template. Together, these make for a very interesting way to capture a location's data on one page. If you are the type to create lots of notes on your campaign setting as inspiration strikes, having a template that you can use is often very helpful. I've combined these together into one template below, and added my own version of the encounter table format as a reference.
Location Name: What is this location called? (Official name may be different.)
Ambiance: How does this location look and feel?
History: What elements of this location's history provide adventure ideas?
Encounters: What flavor of encounters could be found here?
Treasures: What special treasures may be found here?
Hooks and Hotspots: What adventure hooks and special sub-locations can be found here?
Life Level: How much diversity exists in plants and animal life in this area? (High, Medium, Low)
Hazard Level: How dangerous is it to live here? (High, Medium, Low)
Difficult Terrain Density: How difficult is it to move around in this area? (High, Medium, Low)
Resource Level: How significant and desirable are the local resources? (High, Medium, Low)
Herbivores: What eats the environment here?
Predators: What eats the other creatures here?
Scavengers: What eats the dead here?
Hazards: What makes it lethal to live here?
Humanoids: What humanoids live here?
Exotic: What supernatural or unusual creatures exist here?
2d6 Encounter 2 Rare 3 Uncommon 4 Uncommon 5 Common 6 Common 7 Common 8 Common 9 Common 10 Uncommon 11 Uncommon 12 Rare
Here's an example of the template filled out for a location I may be using in a future fantasy campaign.
Location Name: Mazhtekha Valley
Ambiance: The ruins of a crumbling granite ziggurat break through the foilage of lush jungle valley.
History: Many generations ago, a blood cult brought captured vampires to this isolated site to sacrifice them to a dark blood god. A failed summoning ritual cursed the cultists with an overriding lust for blood, and they destroyed one another trying to sate their thirst.
Encounters: Many encounters in this area focus on the twin themes of blood and ancient curses.
Treasures: The Blood Rubies of Mazhtekha, a collection of five enchanted fist-sized rubies, are hidden within the ziggurat.
Hooks and Hotspots: A huge vampiric blood ooze patrols the jungle floor at night, retreating to the ziggurat during the day. A cabal o vampires seek the remains of their former sires (or perhaps an item he was known to carry), and the sire was rumored to be among the vampires used in the failed rite.
Life Level: Medium (mostly plants, as creatures with blood must be very quick or flyers to avoid being eaten)
Hazard Level: High
Difficult Terrain Density: Medium
Resource Level: Medium
Herbivores: insect swarms, flying snakes, bats
Predators: stirges, jaguars, assassin vines
Scavengers: ghouls, carrion crawlers
Hazards: huge vampiric blood ooze
Humanoids: degenerate cultist descendants (treat as cavemen),
2d6 Encounter 2 Vampire(s) 3 Carrion Crawler(s) 4 Ghouls 5 Stirges 6 Bat Swarm 7 Centipede Swarm 8 Flying Snake(s) 9 Assassin Vine 10 Jaguar 11 Cavemen 12 Vampiric Blood Ooze
The nice thing about this particular template is that it really isn't locked into the fantasy genre, so you could, in theory, use it for any setting you may be working on. Ultimately, it should be used for locations that are fairly homogenous. If you use this in a Sci-Fi campaign, I'd suggest that you not use the template for a planet, and instead use it for a region on the planet's surface, or perhaps a complex or settlement instead.
Hope This Helps,