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Single-point urban interchange
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====Continuous green T (or seagull) hybrid==== There is also a variant of the inverted SPUI, which can be used when a side road ends at, rather than crossing, a free-flowing road. In this variant, one carriageway of the free-flowing road is grade-separated from the side road, as with a typical inverted SPUI, while the other carriageway of the free-flowing road is at-grade with but still separated from the side road, as found in a [[seagull intersection|continuous green T- (or seagull) intersection]]. There is one such interchange in [[Pultney Township, Belmont County, Ohio]], between [[Ohio State Route 7|State Route 7]] (SR 7) and [[Interstate 470 (Ohio–West Virginia)|Interstate 470]] (I-470) at {{coord|40.047657|N|80.733542|W|}}. The ramps leading to and from I-470 run west of, but are not directly connected to, SR 7; these ramps form the "side road" at this interchange. The southbound carriageway of SR 7 bridges over the interchange, while its northbound carriageway remains at-grade. SR 7's left on- and offramps run between its carriageways, meeting the I-470 ramps at an at-grade intersection. The I-470 ramps proceed to a [[trumpet interchange]] with I-470. I-470 itself bridges over both carriageways of SR 7 a short distance north of the I-470/SR 7 ramps' intersection. This design was likely chosen not for cost savings but because the northbound carriageway of SR 7 is bordered by railroad tracks, commercial properties, and the [[Ohio River]] and because I-470 bridges the river just east of SR 7—a more conventional interchange design was likely more difficult to achieve. There is another such interchange in [[Millvale, Pennsylvania]], near [[Pittsburgh]], at the junction between [[Pennsylvania Route 28]] (PA 28) and the [[Washington Crossing Bridge (Pittsburgh)|40th Street Bridge]]. The northbound carriageway of PA 28 passes under the interchange, with lefthand ramps meeting at the bridge (the northbound entrance ramp does not provide direct access to PA 28). The southbound carriageway of PA 28 has a continuous green T-intersection with the bridge.<ref name=ppg>{{cite news|last=Schmitz|first=Jon|title=Whole new Route 28 beginning to emerge through construction|url=http://www.post-gazette.com/pg/11271/1178066-53.stm|date=September 28, 2011|access-date=August 4, 2015|work=[[Pittsburgh Post-Gazette]]|archive-date=October 6, 2011|archive-url=https://web.archive.org/web/20111006091526/http://www.post-gazette.com/pg/11271/1178066-53.stm|url-status=live}}</ref> A similar interchange exists in [[Coal Grove, Ohio]], at the junction of [[U.S. Route 52 in Ohio|U.S. Route 52]] (US 52) with the [[Ben Williamson Memorial Bridge]] and the [[Simeon Willis Memorial Bridge]], which cross the [[Ohio River]] and lead to and from [[Ashland, Kentucky]], respectively. The eastbound carriageway of US 52 passes under the interchange, with lefthand exit and entrance ramps to the bridges. The westbound carriageway of US 52, which narrows to one throughlane, has a continuous green T-intersection with the bridges. The ramps cross each other [[wikt:at-grade|at-grade]], with a [[traffic light]]-controlled intersection.<ref>{{ cite web | url = http://www.dot.state.oh.us/Divisions/Planning/TechServ/TIM/Documents/SLD/pdf_files/lawus0052r.pdf | author = Technical Services | title = Straight Line Diagrams: Lawrence County, US 52 | type = PDF | publisher = [[Ohio Department of Transportation]] | access-date = February 14, 2019 | archive-url = https://web.archive.org/web/20160320113505/http://www.dot.state.oh.us/Divisions/Planning/TechServ/TIM/Documents/SLD/pdf_files/LAWUS0052R.pdf | archive-date = March 20, 2016 | url-status = live }}</ref> An interchange, like that in Millvale, Pennsylvania, formerly existed at the junction of SR 7 and [[Ohio State Route 822|SR 822]] at the now-demolished [[Fort Steuben Bridge]] in [[Steubenville, Ohio]]. The northbound carriageway of SR 7 passed under the bridge, with lefthand ramps meeting the bridge approach, while the southbound carriageway had a continuous green T-intersection with the bridge.<ref>{{ cite web | url = http://www.dot.state.oh.us/Divisions/Planning/TechServ/TIM/Documents/SLD/pdf_files/jefsr0007r.pdf | author = Technical Services | title = Straight Line Diagrams: Jefferson County, SR 7 | type = PDF | publisher = [[Ohio Department of Transportation]] | access-date = August 4, 2015 | archive-url = https://web.archive.org/web/20131027062044/http://www.dot.state.oh.us/Divisions/Planning/TechServ/TIM/Documents/SLD/pdf_files/jefsr0007r.pdf | archive-date = October 27, 2013 | url-status = live }}</ref>
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