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Lots of them! Pokemon go has a few main biomes with lots of other factors to determine what spawns. Main biomes are grass, city, mountain, and water.

Then you have other tags for things like parks and paths, which give special spawn points. Parks have rotating habitats for one particular species and can have EX gyms. Paths will spawn Pokemon along them with a few unique species.

Regional spawns occur as well, with some continents or countries having one or more special species unique to it. And rather than a strict limit, some species are much more common in certain latitudes.

Beyond that are some tags that prevent spawns, like military bases or wetlands, places you aren't encouraged to just walk around.

A list of tags from Reddit

Notes on how POGO uses these:

Blocked Spawn areas http://overpass-turbo.eu/s/r42

Nest Locator http://overpass-turbo.eu/s/r43

Nests that require paths http://overpass-turbo.eu/s/r44

OSM Influences Nests and Blocked Spawns (a work in progress)

Nests

Confirmed

leisure=park

leisure=garden

leisure=golf_course

leisure=recreation_ground

boundary=physiogeographical

landuse=grass (may need secondary tag to be a nest)

Possible

landuse=recreation_ground

leisure=playground

landuse=village_green

leisure=pitch

boundary=national_park

Paths

highway=footpath

highway=path

highway=cycleway

highway= sidewalk

highway=footway

route=bicycle

route=hiking

route=foot

network

Creates Nests if Paths present

Confirmed

landuse=farmland

landuse=farmyard

natural=scrub

natural=heath

landuse=meadow

Possible

natural=moor*

natural=grassland

natural=fell

natural=bare_rock

natural=scree

natural=shingle

natural=sand

natural=mud

natural=valley

natural=rock

natural=stone

natural=arete

natural=beach

landuse=greenfield

(*Deprecated or incorrect tag)

Blocked Spawns

Blocks Spawns without Paths

Confirmed

natural=wood

landuse=forest

natural=forest*

Possible

landuse=orchard

(*Deprecated or incorrect tag)

Blocks all Spawns

Confirmed

landuse=construction

landuse=military

landuse=quarry

landuse=railway

landuse=landfill

aeroway=runway

aeroway=taxiway

amenity=school

highway=motorway

highway=trunk

highway=primary

highway=secondary

highway=tertiary

Water tags, unknown if surrounding spawns are water influenced

natural=wetland

wetland=

natural=glacier

natural=marsh*

(*Deprecated or incorrect tag)

Possible

amenity=daycare

amenity=kindergarten

Water

Effects biomes on edges. Blocks spawns away from land unless crossed by route=ferry?

Confirmed

landuse=basin

landuse=reservoir

natural=coastline

natural=spring

natural=water

water=lake

water=pond

water=reservoir

water=basin

water=canal

water=river

natural=waterway

waterway=river

waterway=riverbank

waterway=stream

waterway=canal

waterway=drain

waterway=ditch

man_made=water_tower

Possible

landuse=salt_pond

natural=bay

waterway=wadi

waterway=drystream

waterway=fairway

waterway=dock

waterway=boatyard

waterway=dam

waterway=weir

waterway=stream_end

waterway=waterfall

waterway=lock_gate

water=lagoon

water=reflecting_pool

water=fish_pass

water=oxbow

water=lock

water=moat

water=wastewater

water=stream_pool

Possibly Effects Biomes Only

natural=peak (Mt Moon biome forms around peaks)

landuse=industrial

landuse=commercial

landuse=residential

landuse=retail

Does not block spawns or create nests but otherwise unknown

landuse=cemetery

landuse=port

landuse=depot

landuse=garages

amenity=grave_yard

Boundaries

May influence all nests needing paths to spawn within that area

boundary=administrative

boundary=historic

boundary=maritime

boundary=political

boundary=postal_code

boundary=religious_administration

boundary=protected_area

boundary=national_park

boundary=physiogeographical

Unknown Effects

Area

natural=hot_spring

natural=volcano

natural=sinkhole

natural=tundra

landuse=brownfield

landuse=allotments

landuse=greenhouse_horticulture

landuse=plant_nursery

landuse=vineyard

geological=moraine

geological=outcrop

geological=palaeontological_site

Lines

natural=ridge

natural=cliff

natural=saddle

natural=tree_row

Nodes

natural=geyser

natural=tree

natural=cave_entrance

Some tag info from Reddit regarding paths and spawn blocking:

1. Lines tagged highway=footway that also carry the tag bridge=yes do not generate additional spawn points. Critically, this encompasses all boardwalks, which are correctly tagged bridge=boardwalk.
2. Lines tagged highway=footway do not provide a spawn point exception through the area blocked by natural=wetland as they do for natural=wood. It's possible that this is an extension of the issue with bridge=yes – I have no local examples without both tags.
3. Areas tagged landuse=basin block all spawn points, despite being used correctly to tag the contemporary practice of building a stormwater retention system beneath a city park. These areas are rendered as water in-game, but do not seem to influence Water spawns, although more data would be helpful in determining this. (OSM also has issues rendering basins.)
4. Areas tagged leisure=nature_reserve do not nest. Could be intent, could be oversight, but seems like an odd exception, as the distinction between a park and a preserve is fluid – at least in the US. The same is true for areas tagged landuse=winter_sports, the correct tag to describe a ski resort, and areas tagged leisure=dog_park.
5. Areas tagged amenity=prison do not block all spawn points. Since this is the correct way to tag a prison or jail – which is to say, a high-security facility where people probably shouldn't be chasing Pokémon – this seems wrong.
6. Lines tagged waterway=river, waterway=stream, and waterway=ditch are not rendered on the map despite influencing Water spawns in nearby spawn points. The same is true for areas tagged natural=wetland and points tagged amenity=fountain.
7. Lines tagged power=line and power=minor_line do not influence Electric spawns in the way that streams do with Water Pokémon. More of a missed opportunity than anything. You could say the same with railway=rail and Steel or any of the more specific OSM building tags the game references to seemingly no effect: leisure=stadium, amenity=cinema, tourism=hotel, and so on.
8. Lines tagged highway=track show up visually as paths, despite being intended to represent vehicle tracks that fall short of the qualifications for being an unpaved road. They do not generate additional spawn points, so this is assumed to be an error with the in-game renderer.
9. Lines tagged highway=service and service=driveway render as roads on the map, which are not to scale. This is especially glaring if houses and garages are mapped. Ideally, there probably should be a thinner style of road for all service roads, tracks, living streets, or any other highway designation where vehicles are likely to encounter pedestrians.