The Spaghetti Bowl Interchange is a colloquial name for complex freeway interchanges characterized by their intricate, tangled network of ramps resembling a bowl of spaghetti when viewed from above. This nickname is commonly applied to several major interchanges worldwide, particularly in the United States, where high traffic volumes and multi-level designs create convoluted layouts. The term emphasizes the visual complexity and navigational challenges these structures present to drivers.
The most prominent Spaghetti Bowl Interchange is located in downtown Las Vegas, Nevada. It serves as the system interchange between Interstate 11 (I-11) / U.S. Route 95 (US 95), Interstate 15 (I-15), and U.S. Route 93 (US 93). Additionally, it includes a service interchange with Martin Luther King Boulevard. This interchange handles over 300,000 vehicles per day as of 2019, making it one of the busiest in the region.
Construction of the original Spaghetti Bowl Interchange began in the mid-1960s by the Kiewit Corporation and was completed by 1968. It connected I-15 to the newly developed Las Vegas Expressway, which carried the relocated US 95 from Bonanza Road. The expressway was later renamed the Oran K. Gragson Freeway in honor of a former mayor of Las Vegas. Initially a mile-long spur to Las Vegas Boulevard in downtown, it evolved into a bypass for US 95 traffic around Rancho Drive.
A major reconstruction occurred between 1999 and 2000 to accommodate growing traffic demands and improve safety. The redesign featured additional lanes, better signage, and more efficient ramp configurations. Despite these upgrades, the interchange remains notorious for congestion, especially during peak hours and events in Las Vegas. It has been cited as one of the most dangerous stretches of roadway in the city due to its complexity, with frequent accidents reported from improper lane changes and high speeds.
The name "Spaghetti Bowl" originated from its overhead appearance, a common moniker for similar interchanges across North America, such as those in Salt Lake City, Reno, and Chicago. In Las Vegas, it has become a staple in local traffic reports and urban lore.
Another notable Spaghetti Bowl Interchange is in Reno, Nevada, at the junction of Interstate 80 (I-80), Interstate 580 (I-580), and U.S. Route 395 (US 395). Construction started in 1969 and serves over 460,000 vehicles daily. Key improvements include ongoing projects like the Xpress Upgrade, which began in the late 2010s to widen lanes and add auxiliary ramps. Historical milestones include paving 180,000 square yards of new concrete by 2025 and reopening ramps such as the southbound US 395 off-ramp to Parr Boulevard. Future plans extend to 2039, focusing on enhanced connectivity for the North Valleys area.
In Chicago, Illinois, the Circle Interchange, also known as the Spaghetti Bowl, connects the Eisenhower Expressway, Kennedy Expressway, and Dan Ryan Expressway. Built in stages from 1955 to 1962, it features concentric circular ramps and is one of the nation's busiest traffic nexuses. A major reconstruction in the 2010s, renamed the Jane Byrne Interchange, addressed aging infrastructure and improved flow.
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