There is a redoubt located beneath the world trade center. It was installed after the explosion set off in the mid 90's by a group of terrorists. The repair work was perfect cover for the installation of the facility. Although not considered an official totality concept installation, it was used by the government officials for quick transportation to and from Washington DC.
This gateway was used by the Exiles to enter the intact city of New York using Lakesh's Omega Path concept, by using the gateway to act as a time trawler device. It was also used by the group to enter the remains of New York city in Iceblood on their way to retrieve part of the Chintamani stone.