You decide that there's certainly not going to be anything of value left in the 300-year-old lab, and decide to head straight for the exit. Going as fast as you possibly can -- some kind of monster may have taken up residence here, and you are not ready for any encounters.
Your sense of unease abates as you enter the front lobby. The place is trashed, looking like a violent struggle -- or several -- took place here. But the way to the doors is clear, at least. They open outward, manually, made of thick glass in steel frames. Apart from a spiderweb of cracks in the left door, they're still in working order and open easily at your touch.
And now you're outside, breathing deeply of the cool breeze; it blows from the north with a strangely sweet scent. At least you're free of the stale, musty air of the lab, and of the sense of being watched. It seems to be dusk -- at least you hope the long shadows and red sky are not permanent features of this strange new world. In front of you is a wide street, with ruined buildings across it and to your left and right. However, you also notice a couple of things of interest.
To the north -- your left -- the street climbs a shallow incline. In that direction, you believe, is a park, and it seems almost to be invading the city -- increasingly thick ivy covers the buildings; grass is eating the asphalt; bushes and a few young trees push out of split sidewalks. A billboard has been propped against a ruined storefront, crudely painted over with an arrow pointing up the street towards where the sweet scent is blowing from. It is partially covered by vines, allowing you to only read part of it.