This map depicts the area around Ilchester Tunnel (black) and the now disused original Old Main Line alignment (green) it bypassed. Ellicott City is off the map to the left and Relay to the right. The Patapsco River winds through the valley, with Howard County south and Baltimore County north.

The dashed red line represents River Road before the floods of Tropical Storm Agnes washed it away in 1972. The road has not been rebuilt. The gray line is a hiking path from South Hilltop Road (where the power lines cross overhead) to the rocks above Ilchester Tunnel, down to the site of Bloede Dam.

Instead of going through this hill as does the Ilchester Tunnel seen in the distance, the original alignment curved around it, roughly as marked by the green line.

Since B&O was a pioneer, it was forced to learn track design via trial and error. Three types of early B&O track are depicted on a trailside sign. Along the disused right of way here, we find stone stills (stringers) as drawn at left. Some remain extant, as seen below.

Despite the passage of over 100 years, the ballast left behind has prevented new tree growth along the old right of way. And, in at least one spot, you can see one of the most curious railroading artifacts anywhere in the world: B&O's original stone stringers.

For some of its earliest tracks, instead of wood cross ties, the railroad employed stone with parallel thin rails affixed to it because stone was deemed more durable and long lasting. Indeed, this photo is evidence of that, but B&O quickly discovered that the stiff granite was also less cushioning.

All but one contractor employed by B&O to build the OML was bankrupted by the unexpectedly high cost of building the stone track. Work progressed too slowly as well, and eventually the company relented, allowing the second track along this route to be constructed with wood ties, similar to those used today. They learned the wood-style track construction could be completed 10 times faster, and that sealed the fate of the stone.

The holes indicate where iron strap rail (B&O called it plate rail) was affixed. This stringer exhibits two rows of holes, leading to the belief it had been part of a switch. You can still see the grooves left behind by the iron strips.

Strap rail was employed because it used less iron than other designs; iron was in short supply and most had to be imported from mother England. The strap rail had the frightening reputation of peeling off the granite, then curling up and piercing into cars that rolled above; these were called "snakeheads". Still, B&O stuck with strap rail for about 20 years, then frugually reused it on sidings and in yards into the 1860s.

The B&O strap rail segment I donated to a museum measured roughly 1/2 inch thick and 2 1/4 inches wide with a nail 4 1/2 inches long. Nail holes were spaced 18 inches apart.

As if to forget their disappointment with stone, B&O left little documentation to tell us how track switches were implemented with the granite stringers. Harold Dorsey kindly contributed this sketch of a stringer shown in the prior panel.

Per the sketch, granite stringers found in the vicinity of the switch range in length from 36 to 65 inches. Iron strap rail was nailed to the granite at a common interval of 18 inches, though this distance was adjusted where needed, such as at switches. Wear patterns on the stones suggest wheel flanges of passing cars had rolled there.

A doubly-nailed join (or joint) bar was placed in a recess under the strap rail where segments met. For sturdiness, I suspect builders tried to avoid placing the meeting spot of rail segments directly above where two stone stringers met below. Many surviving stringers show iron oxide staining at joint bar (aka join plate) recesses like that at right.

The bar in the main photo shows no obvious holes or nails. I suspect the nails were broken off and then rust filled the holes.

Along some track stretches, B&O used wood intead of stone to support iron strap rail.

This item was purportedly displayed at 1927's Fair of the Iron Horse. Its basic design matches that of an iron strap rail on wood stringer, except there appears to be wood grain on the top of what was normally the iron portion. Typed information on the back of the photo reads, "Old wooden rails, first to be used on the old main line of the Baltimore and Ohio - 1830 - recently found in old farm house and barn in Carroll County, Maryland."

There is no record of B&O using wood nailed to wood stringers as track. Wood would splinter under the wheels of heavy trains. This might be a mockup made to merely illustrate the general track appearance.

B&O mounted the wood stringers on cubic stone blocks like the pair here. Most such blocks are now deeply buried and revealed only by floods or track work. These are the only ones I've seen in situ.

This culvert was good for comparisons to others. It was located along the abandoned right of way, not far from the stone stringers above. The culvert hadn't seen any maintenance for about 100 years, but, except for plant overgrowth, appeared in good shape.

Sadly, this original culvert was torn out and not restored by the Patapsco Relocator project that removed Bloede Dam.

Looking backward, the Grist Mill Trail Extension constructed in 2003 climbs to join the original right-of-way. The present-day trackage is inside Ilchester Tunnel bored through the hill on the left.

At the path intersection, the stringers were torn out and now serve as a curb of sorts. Behind us, on the way to the Patterson Viaduct, the stringers were simply paved over, preserving them for future archeologists who will someday marvel over our "stone age" of railroading.

Except, while removing Bloede Dam, the Maryland Dept. Of Natural Resources rerouted sewer lines in the vicinity from their current location to underneath Grist Mill Trail, and tore out the paved-over stringers. This has been one of few locations that preserved the original history of such track construction techniques. Fortunately a stretch closer to Ilchester Tunnel remains undisturbed.

Detour: more stringer photos

Easily heard from the path was the crash of water over Bloede Dam. Bloede is pronounced "Bler-dah" according to a friend of the family of Victor Bloede, founder of Patapsco water and power companies. The dam officially opened November 28, 1907, the date upon which its internal generators began cranking out electricity for the area, enough that during 1913 the Baltimore Gas & Electric (BGE) Co. acquired it. According to BGE, the dam's construction was unique in that it was hollow with the water wheels and generators housed inside. The dam was upgraded with fish ramps in the 1990s; I am not sure when it stopped generating power. The concrete pipe on the right is a storm or sanitary sewer. Bonus points if you spotted the turtle lounging on the rock.

This dam was removed during 2018, see Bloede Dam removal. With the push to "go green" that effort might have been better spent restoring the dam's capability to generate hydroelectric power. The popular McKeldin Falls upstream is unlikely to be removed, so removing Bloede Dam accomplished little. The invasive snakehead fish has now reached upstream, however.

Courtesy JD Hiteshew below are other views dating from 1973 (the spring after Agnes floods, note the scoured valley and remains of River Road on left), plus two from 1975 (more flooding, probably due to the remains of Hurricane Eloise in late September that year):

Immediately upstream from here, the river squeezes through a narrowing valley that amplifies flood effects at the expense of bridges.

A sharp curve of the Patapsco River within the narrow valley at Ilchester encouraged B&O to cross the river here.

This is the only photo I have seen of the Patterson Viaduct in its original, four-arch, masonry form. Most of it would be destroyed in the terrible flood of 1868 (some sources report 1866). Notice how Patterson's middle stone piers were not quite parallel to the flow of the river. Such misalignment causes erosive eddies that may have contributed to the bridge's demise. Stone bridges are otherwise extremely durable, witness Roman aqueducts that have stood for thousands of years.

It appears some type of structure is obscuring the view of the far side's arch. B&O's frame Ilchester Station was later erected near that spot. The houses at distant left represent the unfulfilled hope of George Ellicott that B&O would make his tavern and hotel a major stop of the railroad. That did not happen and, as will be seen on the next page, he would later sell the property to the Catholic Church.

This temporary wooden structure filled in for the viaduct portions lost in the 1868 flood. This WM Chase photo was snapped from a bit downstream of the 1859 view above. It appears to show the viaduct with an iron Bollman bridge under construction: note the dark trapezoidal posts typical of the Bollman design at the far end of the bridge. Compare this image to the engraving shown on page 390 of Impossible Challenge II.

At right, only rubble remains of what likely was a stone retaining wall. As we'll see below, it was rebuilt around 1874.

The yellow stripe at bottom left designates the middle of River Road, or rather what remained of it more than 35 years after Tropical Storm Agnes had her way with the Patapsco Valley. The disused B&O RoW we're following rides the opposite bank of the river (right), and through the trees you can spy a modern Patterson Viaduct footbridge and further upstream the active steel railroad bridge. River Road's dregs here were removed during the 2010s.

Frequent contributor Dave Hiteshew shares with us the photo at right captured from roughly the same location in April 1973. It illustrates the ferocity with which during the prior June Agnes tore asunder what both nature and man had assembled. In the distance at center left appears to be the remaining stone walls of George Ellicott's Ilchester tavern. A note about the road striping: prior to the early-1970s, a single yellow line, rather than double, had been the USA standard to separate lanes of opposing traffic, with white dashes where passing was allowed. Few later movies set during the period get this nitpicky road detail correct.

This photo is one of my favorites. It was snapped from the east bridge abutment of the remains of the Patterson Viaduct. Some reports say the Patterson Viaduct was the first railroad bridge in the world, with its cornerstone laid May 6, 1829 and first crossing later that year on December 4th, with completion a few months before B&O's Carrollton Viaduct. Across the Patapsco River on the Howard County side is the west bridge abutment.

Now the railroad spans the river by means of the bridge seen upstream on the right. The picture at right courtesy JD Hiteshew illustrates Hurricane Eloise's flooding in 1975 as seen from the same spot.

Link: Hurricane Eloise history

After about a century of rest, the Patterson Viaduct began carrying traffic again. The footbridge seen here nearing completion opened on October 18, 2006.

Patrick O'Donnell kindly contributed this photo, and wrote:

"I had the opportunity to work on that new footbridge and have found the history of the area fascinating - thanks to your website. The plans of the new cable-stayed footbridge show that there's (less than an inch) variance between the elevations of the opposing abutments. Quite remarkable for abutments built in the late 1820s, 164 feet apart from each other, and their excellent condition as well. No modification was needed to accompany the new bridge - other than placing additional tower pedestals atop each abutment.

"I was contacted by the company putting in the footbridge for pictures of the existing suspension footbridge about a mile down river. The plan was to do something like the suspension bridge. When the owner found out that a Bollman Truss once existed at the Patterson Viaduct it became clear that only a cable-stayed bridge with a stiffening truss will do. The diagonal cable stays are to emulate the diagonal members of the Bollman Truss. The beauty of cable bridges in general is that they appear light and airy and unobtrusive."

Link: lots more photos of this by Patrick