install.packages("ggplot2")
library(ggplot2)
con1<-url("http://kanggc.iptime.org/book/data/Map.RData")
con2<-url("http://kanggc.iptime.org/book/data/mapJeju.RData")
load(con1)
load(con2)
ggplot()+geom_path(data=map, aes(x=long, y=lat, group=group))
ggplot()+geom_path(data=map.jeju, aes(x=long, y=lat, group=group))