highway, often as long as . This is because the ramp is not isolated from the mainline, only one lane in width, is a low-speed ramp (marked as a ramp), and is relatively short () while carrying a high volume of truck traffic south to Indiana from North Avenue. Additionally, the sudden appearance of the exit tends to cause accidents when cars in the center lane try to aggressively turn into the right lane, particularly at the mouth of the I-294 exit. Finally, there is a dangerous high-volume weaving situation at the end of the ramp to I-294 with southbound I-294 traffic exiting to westbound I-88. , there are no plans to overcome any of these problems with new construction. The western of this section are blacktop, while east of IL 83 (exit 10) the original concrete is still in place. Tri-State Tollway to Austin Boulevard This section of I-290 is long, and it runs from Hillside to the western border of Chicago. This section is sometimes referred to as the "Avenues". , it is the third-most-congested stretch of highway in the Chicago metropolitan area, behind the Jane Byrne Interchange area and the intersection of the Dan Ryan Expressway and Chicago Skyway. It is known for having a high volume of traffic on ramps through the Avenues, and high volumes of traffic on left-side ramps in Forest Park and Oak Park. I-290 runs above-grade west of Mannheim Road and at- or below-grade east of Mannheim Road. Eastbound at Mannheim Road (exit 17), the highway splits into two express and one local lane; they are joined by two onramps from I-88 and form express lanes three lanes wide and local lanes to Mannheim Road two lanes wide. After Mannheim Road, the highway immediately narrows to three lanes in width, causing mile-long () backups. It remains three lanes to Austin Boulevard. Westbound, I-290 merely is three lanes wide to Mannheim Road and then four lanes wide to the I-88/I-290 split. Exits at Harlem Avenue (exit 21B) and Austin Boulevard (exit 23) are inverted single-point urban interchanges (inverted SPUIs), with left offramps and onramps. These cause backups as trucks switch lanes to exit and a large volume of traffic enters on the left side of the highway. In 2001–2002, this section between milemarkers 15 and 18 was reconstructed in the first phase of an attempt to untangle the "Hillside Strangler", adding the local