Villages and Ballfields

I was reading about Irasburg today, and learned that from 1812 - 1886 it was the shire town of Orleans County. That made some sense to me - I’ve always thought it was a pretty grand place, up there on that plateau.

One of the reasons I like it so much is the central ballfield on the town green. Lots of villages in Vermont have the town green, but few nestle a ballfield into the back corner.

I got to thinking - is this the closest town center to a ballfield in all of Vermont? The town I grew up in - Grafton - also has a ballfield close by, but it’s a little bit hidden, and up a few hundred feet from the store.

Let’s use OSM to try and help us answer this question.

Data

First we’ll use overpass turbo to export the OSM data.

Places:

[out:json][timeout:25];
node["place"]({{bbox}});
out geom;

Ballfields:

[out:json][timeout:25];
nwr["sport"="baseball"]["leisure"="pitch"]({{bbox}});
out geom;

We’ll also download natural earth for a state of Vermont shape:

wget https://www.naturalearthdata.com/http//www.naturalearthdata.com/download/10m/cultural/ne_10m_admin_1_states_provinces.zip
unzip ne_10m_admin_1_states_provinces.zip

Then let’s load everything into PostGIS:

ogr2ogr -f Postgresql "PG:dbname=charliehofmann" ne_10m_admin_1_states_provinces.shp \
  -where "name = 'Vermont'" -t_srs "EPSG:32145" -overwrite -lco GEOMETRY_NAME=geom -nln vermont

ogr2ogr -f Postgresql "PG:dbname=charliehofmann" ballfields.geojson -t_srs "EPSG:32145" \
  -lco GEOMETRY_NAME=geom -nln ballfields
ogr2ogr -f Postgresql "PG:dbname=charliehofmann" populated_place.geojson -t_srs "EPSG:32145" \
  -lco GEOMETRY_NAME=geom -nln place

PostGIS

Now the fun part - let’s find all the places and ballfields within Vermont, then find the top 10 that are closest to each other.

SELECT *
FROM (
  -- find the closest ballfield to each Vermont place,
  -- as well as the distance
  SELECT
     DISTINCT ON (vermont_place.ogc_fid) vermont_place.name, round(ST_Distance(vermont_place.geom, ballfields.geom)::decimal, 0)  as dist
  FROM ( -- Vermont places only
    select place.ogc_fid, place.name, place.geom
    FROM place
    JOIN vermont
    ON ST_Intersects(place.geom, vermont.geom)
  ) vermont_place, ballfields
  ORDER BY vermont_place.ogc_fid, ST_Distance(vermont_place.geom, ballfields.geom)
) place_ballfield_pairs
ORDER BY 2 -- order by distance to find the top 10 closest
LIMIT 10;

And the results:

Irasburg: still undefeated 👑

OSM place point in yellow, OSM ballfield location in pink. If anything the 108 m measurement is too large - it really is right in the center of town.