The Istrian Y (Croatian: Istarski ipsilon) is a highway network in the Croatian highway network & TEN-T network, maintained by BINA Istra (1995 - at least 2027). It consists of 2 sections arranged in a shape similar to the alphabetical letter 'Y', located in the Istria County:
The A8 is a 64.21 km (39.90 mi) long branch which starts at Matulji in Primorje-Gorski Kotar County and finishes in Kanfanar interchange, at the crossing with the A9. The branch was initially built as a single carriageway limited-access road, but the part between Kanfanar and Pazin was projected as a dual carriageway, so all the objects on the road are already prepared for a conversion to a motorway.
The most prominent feature of this branch of Istrian Y is the 5.4 km (3.4 mi) long Učka Tunnel, the third longest tunnel in Croatia. The tunnel was opened in 1981 and is the main road that connects the Istrian peninsula with Rijeka and the rest of Croatia (and the only road for vehicles over 5 tonnes[1]). The tunnel is tolled within a closed toll collection system with the rest of the network.
The first part opened as full motorway, from Kanfanar to Rogovići, was opened for traffic in 2011. Then, sections between Rogovići - Cerovlje, Cerovlje - Lupoglav, and Lupoglav - Vranja, opened in consecutive years from 2020.
The A9 is a 76.79 km (47.72 mi) long branch which connects the Croatian-Slovenian border near Sečovlje with the city of Pula and services the tourist industry on the western coast of Istria. Motorway was initially built as single carriageway limited-access road.
There are two prominent object on this branch of Istrian Y: the viaduct "Limska draga" and the bridge "Mirna".
The viaduct "Limska draga" was built between 1988 and 1991 and was the first part of the western branch of Istrian Y that was constructed. The bridge is 552 m long and the height of the highest pillon is 120 m.
The bridge "Mirna" was opened to traffic in 2005. The bridge represents the crossing over river Mirna and was the most complicated object on the western branch of the Istrian Y because of the swampy terrain around the river. The bridge is 1355 m long and the height of the bridge at the highest point is 40 m. Currently the bridge is being tolled at the price of 14 HRK for passenger cars.
The southern leg of A9 motorway, between Kanfanar and Pula was opened as motorway for traffic in 2010. The northern leg of the A9 motorway, 50 km from Umag to Kanfanar, was opened as motorway for traffic on 14 June 2011, eight months before the deadline.[2][3]
The network, especially the A8 section and Učka Tunnel, is undergoing (as of 2023) and due to further undergo, extensive upgrade & refurbishment works. The works are split into 2 phases, sub-phases, and parts.
Bina-Istra upgrade phases for the Istrian-Y
Completed Phases
Phase 1 + 2A
Construction of a dual-carriageway highway for the following sections:
Construction of a 28 km (17 mi) second carriageway between Rogovići & Vranja
Phase 2B2-1 All works in the 3 sub-parts are estimated to cost a total of EUR 191 million, including the costs for the new Učka Tunnel tube. Part B and the remaining works in this sub-phase are currently still under construction.
Construction of a new 5.63 km (3.50 mi) tube for Učka Tunnel
Construction of a 1.9 km (1.2 mi) second carriageway between Vranja and Učka Tunnel's Istrian portal
Construction of a 0.45 km (0.28 mi) second carriageway on Učka Tunnel's Kvarner portal side
Construction of a new 268.6 m (881 ft) Zrinšćak viaduct
Construction of a new Vranja interchange, including new toll-booth
Construction of new overpasses & underpasses
Construction of a connection road between the carriageways over Učka Tunnel's Istrian portal
Construction of two new toll-booth on either side of the Učka Tunnel
Construction of a new building for the firefighting unit, on Učka Tunnel's Istrian portal side
Demolition of one existing toll-booth on the existing Vranja interchange
Phases Under Construction
Phase 2B2-1
Part A is already complete.
Part B
Construction of a new rest area, on Učka Tunnel's Kvarner portal side
Demolition of the existing rest area, on Učka Tunnel's Kvarner portal side
Other works
Upgrades to the existing Učka Tunnel tube's emergency and signalization systems
Construction of a new Učka Tunnel control room
Construction of new service buildings, on Učka Tunnel's Kvarner portal side
Construction of a new enclosure fence
Whilst the original tunnel tube is being refurbished, it will remain closed (planned until April 2025), and traffic will flow both directions through the new (North) tunnel tube. Traffic flowing Kvarner-bound through the Istria-bound (new) tube during this time is tolled at a temporary structure on the Istrian side. Traffic flowing the correct direction is tolled at a new permanent toll booth on the Kvarner side, the original toll booth having been demolished.
Other Phases
The primary source suggests the works in relation to these sub-phases are not a priority. However, according to sources[4][5] published after this, Bina-Istra will develop these phases, with priority given to Phase 2B2-2. In July 2023 it was announced[6] that works on both these sub-phases would start imminently and last for 38 months until late 2026. Phase 2B2-2 is estimated to cost around EUR 200 million,[7] and when complete, will mean the journey time between Pula and Zagreb is approximately 2 and a half hours. The completion of both these phases will mean the entire network will be a dual carriageway profile.
The official breakthrough of the second Učka Tunnel tube on the 18 September 2023 meant the official start of works for both these phases.[7]
Phase 2B2-2
Construction of a ~10 km (6.2 mi) second carriageway between Matulji & Učka Tunnel's Kvarner portal side
Construction of an improved junction at Anđeli
Construction of drainage and management facilities to reduce the release of harmful liquids from vehicles into the environment[4]
In future, should the planned new Rijeka bypass be constructed, an interchange will likely be constructed on this section[4]
Phase 2B2-3
Construction of a second carriageway for the Mirna Bridge & Limska Draga Viaduct
Remaining Phases
Phase 2B2-4
Construction of emergency lanes for some unprotected sections
