My Discovery: The Ancient Tunnel Of Air Line Railroad

Peter Marteka
Contact ReporterNature's Path & Way To Go

It is my Machu Picchu. My tomb of King Tut. My undiscovered continent.

OK, so I didn't discover the pre-Columbian Inca site high on a hill in Peru. And I didn't find the treasure trove of the Egyptian boy king. And, well Columbus or Vikings discovered North America. But my claim to fame is the discovery of the ancient tunnel of the Air Line Railroad.

Well, that's a little tall tale too. I'm sure others have visited the stone arch tunnel on the Portland/Cobalt line that runs underneath the abandoned railroad line that once took trains thundering past on the way to Boston or New York in the late 1800s and early 1900s. But I like to think I was the first person to discover it like some explorer hacking his way through the jungle or digging under the desert.

Whether you want to call it a stone arch tunnel or culvert or bridge, this is one of the finest examples in the state. Sometimes I feel like writing a letter to the state Historic Preservation Office or the National Registry of Historic Places and get this structure preserved for all time. But the way this was built, it is probably not going anywhere for 1,000 years.

Finished in 1898 - there's a keystone with the date near the top of the tunnel - the structure is perfect. It almost looks like some museum hallway with its smooth ceiling, etched with granite veins. One half expects to pass priceless paintings or headless statues.

The structure is similar to the Vernon Tunnel I wrote about a few weeks ago, except it is twice as big and no cars drive through it. Visitors have plenty of time to walk through and imagine workers hauling the huge chunks of granite from a nearby quarry and putting each piece into place like a huge puzzle.

The 25-foot-tall, 30-foot-wide and 75-foot-long tunnel carries Great Hill Pond Brook known to others as Cobalt Stream under the abandoned tracks. A stone path runs parallel to the brook that was probably used to transport cattle or sheep under the tracks to fields along the Connecticut River.

The tunnel acts as a right-of-way connecting the Middlesex Land Trust's 6-acre Taylor Brook Preserve with the 6-acre Okumsett Preserve to the north of the structure. About a half-dozen abandoned factory foundations dot the banks of the stream and stand in silent testament to the area's industrial past. The Taylor Brook Preserve trail connects with the 80-acre Palmer Preserve, a large field where wildflowers bloom and deer and wild turkeys graze.

So come see what I discovered in the wilds of Portland and Cobalt. It's not an Incan city or a golden tomb, but it is a bit of buried treasure.

Take Route 66 to the intersection of Route 66 and Route 151 in Cobalt center. Turn on Depot Hill Road and bear left on Middle Haddam Road. You will cross over Great Hill Pond Brook after approximately two-tenths of a mile.

There is limited parking on the left and right side of the road. Look for the orange blazes and land trust signs.

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