## Warning: package 'mapview' was built under R version 3.4.2

## Warning: package 'rgdal' was built under R version 3.4.2

## Warning in strptime(xx, f <- "%Y-%m-%d", tz = "GMT"): unknown timezone
## 'zone/tz/2017c.1.0/zoneinfo/America/Los_Angeles'

## OGR data source with driver: ESRI Shapefile 
## Source: "ice_facility_points", layer: "ice_facility_points"
## with 209 features
## It has 44 fields

## OGR data source with driver: ESRI Shapefile 
## Source: "lower_leg", layer: "lower_leg"
## with 4839 features
## It has 9 fields

## OGR data source with driver: ESRI Shapefile 
## Source: "upper_leg", layer: "upper_leg"
## with 1941 features
## It has 9 fields

m