The Gateway City of St. Louis is the epitome of the modern Midwestern metropolis. Missouri's second-largest city is vibrant but laid-back, populous but navigable, historic but still relevant. The city's planners have created an aesthetically beautiful city, with plenty of green space amidst buildings both old and new, framed by the majestic Mississippi and Missouri rivers. And capping it all is the world's tallest man-made monument, the beautiful and iconic Gateway Arch.