Expressways are controlled-access highways, with crossing traffic limited to overpasses, underpasses, and interchanges. Expressways are limited-access roads, with crossing traffic limited to overpasses, underpasses, and interchanges. Achieving such free flow requires the construction of many overpasses, underpasses, and ramp systems. The overpasses along the road consisted of steel girder bridges and through plate girder bridges. The road has two lanes and includes three road junctions, five bridges and four overpasses. Bridges and overpasses can be especially dangerous. Stack interchanges are made up of several overpasses. The city maintains 90 bridges and overpasses. The plan includes new ramps with two overpasses over the expressway. All of the remaining original overpasses and bridges were demolished and replaced with modern works. A year later, construction began on overpasses and ramps at the Farnhurst interchange. Another commonly held misconception is that highway overpasses provide adequate shelter from tornadoes. It featured a full 3D environment, overpasses and tunnels, and much improved graphics. People stopping underneath overpasses block the flow of traffic, putting others in danger. Some have low overpasses that also exclude buses.