The centerpiece of the Houston Downtown Aquarium is the restaurant and the large fish tanks throughout. There is a winding staircase around a huge, vertical fish tank as you make your way to the restaurant upstairs. But even if you don’t eat, you can still sneak in to take a peak at the bottom half. There’s even a souvenir shop just behind it also. Nothing like taking home a stuffed fish after stuffing yourself with fish, I suppose.