Saturday was warm and pleasant, Sunday raw and unpleasant, and today — Ides of March Snow. If Rome had had a few inches that day, Caesar might have stayed home, since the rarity of snow would surely have been a warning not to do any official business. Oh, well.

Except for scattered dirty piles in parking lots, all of the massive February snows had melted by March 14. The March 15 snow will last a few days at most, due to a warming trend predicted for later in the week.

Illinois has a few hills, typically relics of ancient glacial movements. Built on top of one of them, in the village of Lemont, is St. James at Sag Bridge Catholic Church, which got its start in historic times — but still quite a while ago, in the 1830s.

On the slope of the hill is the church cemetery. One side of the hill — maybe better to call it a ridge — is quite steep, yet still sports stones.

The rest of the family had other things to do during the day on Saturday, which as mentioned turned out to be clear and warm, so I headed south for a look around the suburban stretch of Archer Avenue (Illinois 171) between Lemont and the village of Justice.

The urban section of Archer Avenue, “Archey Road,” was the haunt of Mr. Dooley once upon a time, but that’s a matter best left for others to describe (if you feel like paying for access).

In our time, suburban Archer Avenue is a thoroughfare featuring independent and chain restaurants, small office buildings, auto repair shops, liquor stores, churches, schools, municipal facilities, and vast cemeteries. The surrounding forest preserve lands are even larger, the further out you go.

St. James at Sag Bridge is near the junction of Archer Avenue and the north-south Illinois 83, which (to the north) is one of the main transit spines of DuPage County. St. James’ hill also rises near the triple waterways of the Des Plaines River, the manmade Chicago Sanitary and Ship Canal, and an older manmade leftover of the 19th-century canal-building boom, the tiny-by-comparison Illinois & Michigan Canal.

To the south of the church and cemetery is yet another artificial waterway, the early 20th century Calumet Sag Channel, which gives the area its name, Sag Bridge, for a predecessor bridge of the one that now carries 171/83 across the channel. The Calumet Sag connects the Calumet River system with the Sanitary and Ship Canal, which it joins just to the west of the church. It’s a complicated bit of geography that I was only vaguely aware of before I decided to examine this part of Archer Avenue.

Sag? I wondered about that as well. The full name of the canal is the Calumet-Saganashkee Channel. I didn’t know that either, but learning it generated another question, as is often the case. Saganashkee?

Named after a local feature with a modified Indian name, it seems: Saganashkee Slough, which is a lake on forest preserve land in the area.

“A case in point is Saganashkee Slough,” the Chicago Tribune reported in 1994. “It was formerly a huge swamp that extended from west of 104th Avenue to the limits of Blue Island, and its original name, Ausaganashkee, is a Potawatomi Indian word that means ‘slush of the earth,’ wrote former Forest Preserve District general superintendent Cap Sauer in a historical account written in the late 1940s.

“During the construction of the I&M Canal in the 1830s, a feeder ditch was dug in the swamp that helped supply additional water to the canal. The slough was almost destroyed in the 1920s by blasting during the construction of the Cal-Sag Channel. Saganashkee was reconstructed by the forest preserve district, although in much smaller form, Berg said. At 325 acres, it is still, however, one of the largest bodies of water in the district.”

As for St. James, the church was founded to serve workers, mostly Irishmen, who were building the Illinois and Michigan Canal, with the current structure completed in the 1850s. A place to go Sunday morning after Saturday night revels, and sometimes donnybrooks, at least according to Irish stereotypes. I suspect the congregation is a good deal more diverse these days.

It’s a handsome limestone building, built from material from nearby Lemont-Sag quarries, which provided stone for Holy Name Cathedral in Chicago and the Chicago Water Tower besides. I understand the St. James interior is quite beautiful, but it was locked when I visited.

The Our Lady of the Forest grotto on the grounds was, of course, open for a look.

Compared with the church building, the grotto is new, built in 1998 for the for the 165th anniversary of the parish. See grottos when you can.