As NYC is beefing up security on the subway's "ring of steel" in September, the Port Authority is looking to protect the PATH tunnels. According to the Post, contractors are "toiling in the cloak of darkness" for the "hush-hush project" to install flood-prevention gates and bomb-proof metal plates, and they're being pressured to get it done before the WTC memorial opens next year.

The plan to reinforce the tunnels began in 2006, the same year officials stopped a plot to bomb a PATH tunnel. The ensuing report said that if a small explosive went off in one of the tunnels, the Hudson River would flow in at a rate of a million gallons per minute. They are also particularly vulnerable because they "lie in the soft riverbed, unlike other tunnels that are bored through the underlying bedrock."

Port Authority COO Ernesto Butcher insisted that once these repairs get done, there will be nothing to worry about. "The safety of our customers is the Port Authority's highest priority, which is why we have spent over $5 billion since 9/11 upgrading the security systems at our facilities," he said. "Hardening our PATH rail tunnels is one example of that effort."