Roller coasters descended from monumental ice slides — long, steep wooden slides covered in ice — that were popular in 16th- and 17th-century Russia. But historians diverge on the exact evolution of these ice slides into actual roller coasters.

Smart traffic lights are internet-connected vehicle traffic control systems capable of adapting traffic light activity based on information from sensors, edge devices, and video systems. They create a more intelligent traffic management system that reduces congestion and travel times, improves safety, and reduces carbon emissions.

The primary coverage provided under an E&O policy is liability arising from mistakes made in the professional services that you offer. This can be a small dispute with a contractor or a big mistake that results in millions of dollars of damages.

The Channel Tunnel (known as Tunnel sous la Manche in France) — "The Chunnel" — is a 50.46km (31.35 mi) railway tunnel that connects Folkestone (Kent, England, UK) with Coquelles (Hauts-de-France, France) beneath the English Channel at the Strait of Dover.