Facebook invited a small group of reporters to its Prineville, OR data center this week. Most companies don’t even give their own employees access to their data centers (outside of the relatively small group of people it takes to keep the millions of servers inside up and running), but because Facebook open sources most of its server and networking designs, it’s a bit more open to allowing outsiders inside, too. Still, it’s been two years since it last allowed press tour its facilities, so when the company asked us if we wanted to come over for a tour (and lunch), we couldn’t say no.

Prineville was the first data center Facebook built and the complex now consists of three massive buildings (and one smaller one for cold storage). The smallest of the three data center buildings is about 350,000 square feet in size and the newest, which is still under construction, will measure over 450,000 square feet. Each one could easily hold a modern aircraft carrier and still have plenty of room to spare.

Let’s take a look inside one of these buildings.