error: Cannot find cairo.h
Introduction
When installing cairo package for R the following error might be thrown:
configure: error: Cannot find cairo.h! Please install cairo (http://www.cairographics.org/) and/or set CAIRO_CFLAGS/LIBS correspondingly.
The error is generated because cairo.h header file is missing. Follow the steps below to solve this issue on Ubuntu.
Solution
Installing libcairo2-dev package will solve the problem, because it will provide the missing cairo.h file.
This can be verified using the following command:
apt-file search --regex /cairo.h$
It will return the following result:

Now you can install the package:
sudo apt install libcairo2-dev
After installing libcairo2-dev package you might still get the following error (which was the case for me):
fatal error: X11/Intrinsic.h: No such file or directory

In this case install the following package as well:
sudo apt install libxt-dev
NOTE: if you don’t have apt-file installed follow these steps:
sudo apt install apt-file
sudo apt-file update
After that you will be able to run apt-file utility
Conclusion
After following the steps above I was able to install cairo package successfully and hope it will help you too.
Thank you for reading!