TThe USS John Warner, a Virginia-class attack submarine commissioned in 2015, is the US’s third-newest sub.

We got the chance to tour the Warner as it was docked at Naval Station Norfolk.

Named after the former US senator John Warner — but nicknamed the “Sledgehammer of Freedom” by the crew — the Warner can perform a variety of missions for the US Navy, including surveillance, reconnaissance, and search and rescue, as well as launch land-attack missiles, torpedoes, and mines.

The Warner, and submarines in general, is highly classified and rarely seen by the public.

But we got to take a tour of it — here’s what we saw.

Read the full story here.