After the failure of the CTA superstation project, the city began investigating the possibility of a privately constructed airport express service using Block 37 as the downtown endpoint. The city announced in June 2018 that The Boring Company had won a contest to negotiate a contract to construct a high-speed rapid transit link to O'Hare, dubbed Chicago Express Loop, using twin tunnels and electric vehicles based on the Tesla Model X. Funding for construction and operation would be provided completely by the company, and the system would reduce travel time to O'Hare to about 12 minutes.