Creating multiple plots using same dataframe using conditions in ggplot2

[ClawV]

I have a dataframe of airports with year and respective cost. I want to create a single plot showing how the price is increasing over the years for all the 4 airports.

#I can plot for individual airport like below
ggplot((df %>% filter(Airport == 'ORD')), aes(x=year, y=cost)) + geom_line(color = "blue") + geom_point()

#But I am unable to find a reasonable way to have all 4 airports to be displayed in same graph. 
#I tried reshape and melt but the data did not make sense to me.

Dataframe example

Airport	Year	Cost
ORD	2011	100
SFO	2011	150
SJC	2011	200
EWR	2011	250
ORD	2012	150
SFO	2012	200
SJC	2012	250
EWR	2012	300
ORD	2013	200
SFO	2013	250
SJC	2013	300
EWR	2013	350

[williaml]

One of these?

library(ggplot2)

df <- data.frame(
  stringsAsFactors = FALSE,
           Airport = c("ORD","SFO","SJC","EWR",
                       "ORD","SFO","SJC","EWR","ORD","SFO","SJC","EWR"),
              Year = c(2011L,2011L,2011L,2011L,
                       2012L,2012L,2012L,2012L,2013L,2013L,2013L,2013L),
              Cost = c(100L,150L,200L,250L,150L,
                       200L,250L,300L,200L,250L,300L,350L)
)

ggplot(df, aes(Year, Cost, col = Airport)) +
  geom_line()

ggplot(df, aes(Year, Cost)) +
  geom_line() +
  facet_wrap(~Airport)

[ClawV]

Yes this is perfect. I was trying something else. Never figured the solution is so simple. Thanks!