funding grant towards the highway, leading the state to fund the construction despite facing a budget shortfall itself. While the state waited for sufficient funding to commence the project, Boeing constructed a temporary four-lane highway across the factory and parallel to Casino Road in June 1967 to relieve congestion on the latter road; at the same time, the section of Casino Road between Nelsons Corner and the west end of the controlled-access highway section was expanded to four lanes. Construction of the permanent four-lane, controlled-access highway section commenced shortly after Peter Kiewit Sons won the contract in May 1968. The first part of the section, spanning between 20th Avenue West (now Seaway Boulevard) and US 99 (now Evergreen Way), opened on April 23, 1969; the whole section was opened by the end of the year. The western end of Casino Road was truncated at Airport Road, which was extended from 100th Street Southwest to the highway in connecting it with Post Road (now SR 96) at its interchange with I-5; this allowed the excluded section of Casino Road to connect with the rest of the highway. A ramp directly connecting northbound I-5 with westbound SR 526 was subsequently opened on November 13, 1970. When Boeing expanded their factory in the early 1990s to accommodate 777 production, the state of Washington required that Boeing pay for upgrades to the connection between SR 526 and I-5. These upgrades resulted in a direct connection being built to connect SR 526 to I-5 north, whereas previously one had to travel south on SR 527 in order to connect to I-5 north. Additional upgrades included an HOV queue lane for the I-5 southbound on-ramp, and the construction of sound walls along the freeway. Until 2000, SR 526 and 84th St. in Mukilteo was in a continuous alignment. When Paine Field Boulevard (SR 525 Spur) was completed in 2000, the alignment was changed to make the SR 526 expressway and Paine Field Boulevard continuous. The new intersection with 84th St. facilitated the creation of a new Boeing museum, the Future of Flight Aviation Center & Boeing Tour. There were proposals in the 1980s and 1990s to realign SR 525 such that it would intersect with SR 526 near the head of Japanese Gulch. The realignment was intended to facilitate a new ferry dock in Mukilteo and to avoid the population center of the city. While the