Exclusive: This Is the Route Convicts Used to Escape From New York Prison

— -- Newly revealed video shows the route taken by two men who escaped from an upstate New York prison in June.

The video, obtained exclusively by ABC News, features investigators using video cameras, retracing the steps of Richard Matt and David Sweat through a tunnel at Clinton Correctional Facility in Dannemora.

Matt and Sweat squeezed through a catwalk, crossed through underground tunnels, climbed down a ladder and crawled through a pipe, exiting through a manhole outside the prison.

It took the investigators in the video nearly 20 minutes to complete the route used by Matt and Sweat in the escape.

The June 6 escape drew national attention and resulted in a nearly three-week manhunt.

Matt was killed by police 20 days after the escape. Sweat was captured alive two days later.

Authorities have said that the escape was being planned for five weeks – with Sweat and Matt using power tools to cut through the back of their adjacent cells.