Mars is the very first world you see in Destiny's opening cinematic, watching a trio of astronauts leave bootprints in the red dirt as they warily tread toward the the Traveler. At that point in our near-future, Mars looks like it does in all those pictures from the Curiosity rover. You won't see what it looks like post-colonization until later in the game, after you've grown accustomed to fighting through the remains of human civilization on Earth, the Moon, and Venus.
Bungie wants you to feel a sense of loss, and a desire to reclaim humanity's former glory, while you're exploring those places. But that feeling never really manifested for me until I got to Mars' Off-World Transit Station. It's basically an interplanetary metro line - "Your Mars destination solution," according to the wall murals - and I've always been fascinated by subway stations... at least when they don't smell like pee.
The Off-World Transit Station hasn't smelled like pee in centuries, but its purpose is still apparent. The covered area out front, where off-world commuters once sat and stared into their Golden Age iPhones while waiting for the hover-bus, is now crawling with Vex. Aside from the robotic infestation and encroaching sand dunes, the station still looks remarkably intact. Unlike the rusted out Cosmodrome back on Earth or fractured city streets of Venus, it's easy to imagine what this place looked like when it was full of human life.
Past the Golden Age turnstile and inside the station proper, it's pitch black. All you can see is your Ghost's dinky flashlight beam and the glowing cores of patrolling Goblins and Harpies. For a game that's all about bringing Light to the Darkness, Destiny has precious few areas that are literally dark. But the transit station uses it to great effect, letting you get turned around and flanked in a space that you'd have no travel managing if somebody would just turn the damn lights on.
It may be a little extra trouble for us Guardians, but I'd rather they leave the lights off. Splattering glowing white Vex blood (or whatever that fluid actually is) across the tiled walls is particularly satisfying when it gives you a new landmark to navigate by. Best of all, it really is reclaiming mankind's former glory: it's not a metro station if it isn't smeared with bodily fluids.
Now that it's one potential site for farming Reciprocal Runes in The Taken King, the Off-World Transit Station will probably get a bit more crowded. But don't just summon your Sparrow and fly off once you get your MacGuffin. Go a bit deeper, and try to peel your gaze away from the motion tracker now and then. Full of surprisingly intense firefights and subtle clues to the world before, the Off-World Transit Station is a microcosm of my favorite parts of Destiny.