Get aluejakokartat data for Helsinki

hki_aluejako.R

library(sf)

# Define source from where the data is downloaded
source_url <- "https://kartta.hel.fi/avoindata/aineistot/HKI-aluejako-1995-2016-gpkg.zip"
target_dir <- "data"

# Make target dir if it doesn't exist
if (!dir.exists(target_dir)) {
  dir.create(target_dir)
}

# Download and unzip data
download.file(source_url, file.path(target_dir, basename(source_url)))
unzip(file.path(target_dir, basename(source_url)), exdir = target_dir)

# Find path to the target GeoPackage
dsn <- list.files(path = target_dir, pattern = ".\\.gpkg", recursive = TRUE, 
                  full.names = TRUE)

# For all available layers, see sf::st_layers(dsn)
# Relevant for 2016 aluejako:
# suur_2016 
# pien_2016
# perus_2016
# osa_alue_2016

sf_aluejako <- sf::read_sf(dsn, layer = "perus_2016")

# Plot for test
plot(sf_aluejako)