The towers hide in plain sight; there is nothing stiller or more silent on the Lewes, Del., beach. They have been part of this place for so long that people who return year after year to the Delaware resorts hardly notice them anymore. The war against the Germans, not surprisingly, isn't much on peoples' minds these days.

The 11 concrete fire control towers (colloquially known as "submarine towers") have lasted far longer than anyone thought they would when they were built 60 years ago along the Delaware coast, from Cape Henlopen down to Fenwick Island.

Four others went up in Cape May, N.J., under the same authority as the Delaware towers. This was the military installation named Fort Miles, created by the War Department in 1941 on 1,000 acres of what is now Cape Henlopen State Park, the largest and most popular among Delaware's 13 state parks.

Urgency was the watchword at the time: World War II was racing across the Atlantic. The towers were an element in a broad strategy to defend the North American coast: 17 coastal forts were commissioned from Newfoundland to Trinidad for that purpose, to deflect an invasion from the sea.

The mission here was to defend the entrance to the Delaware Bay, for through it the enemy might strike at the chemical plants of the DuPonts, the Philadelphia Navy Yard from where the Victory Ships were sent forth in their thousands, and the oil refineries at Marcus Hook, outside Philadelphia. The latter was an especially tempting target, for all the fuel that enabled the Allied struggle against the Germans in Europe and Africa flowed from there out through the bay. To cut that supply at its source, the Nazis sent their U-boats, individually and in packs. They sank more than 1,000 Allied ships by the war's end, some 400 off the coasts of New Jersey, Delaware and Maryland.

These towers, then, recall that time. But they are not just decaying artifacts of an old war. They are historic, the last expression of "a strategy of coastal defense going back 1,000 years," says Chris Bennett, manager at the Cape Henlopen nature center and a student of these matters. Most of the towers are accessible, which is to say that you can approach them. One is open to the public, and another soon will be. A third fulfills a contemporary mission.

The first of 11
The round tower on Fenwick Island was designated No. 1, according to declassified U.S. Army documents. It is the southernmost Delaware tower, and it is hard to say just how tall it is, because the sand moves now and then and changes that. Eighty feet was the standard.

It is gray or manila, with patches of green that match the variable colors of the sea itself. It plays with the mind: When I first saw it, I thought of anthropomorphic sculptures of another time. At night, when dimly perceived, it is a mammoth chess piece.

Having been raked by the wind, baked by the sun and eaten by salt for six decades, the tower looks its age. Its steel ribs show through. Ivy crawls up it. Brambles crowd its base. Somebody without appreciation for the beauty hidden in all spectacularly ugly things tried to improve it by painting a half-hearted mural on it; they left their lavender palm prints near the sealed-up door.

The tower is surrounded by beach grasses, bayberry and black pines. A path circles it, leads over the dune to the strand. Like the others, the Fenwick tower has a roof that extends over the observation slits near the top. It has smaller openings lower down, to admit light so the troops that manned it could see when they scaled the ladders that led straight up to the high platforms where they stood watch.

It's hard to believe, but the architects of these vertical columns obtruding on the relentlessly horizontal landscape thought they would be difficult to discern what they were from offshore. "They were supposed to look like the cylindrical water towers that served the beach communities," says Bennett, apparently mystified by that presumption.

Northward from Fenwick Island, tower No. 2 stands next to a row of beach houses in North Bethany; towers 3 and 4 are at Dewey Beach, 5 and 6 just north of Rehoboth; the rest are in and around Cape Henlopen. All are on state land.

Nearly all the towers are disintegrating. They were built hurriedly, and their concrete was made with beach sand, which is not the best mix because the grains are too smooth to form a good bond. All but two are sealed, the entrances and lower apertures bricked up. They contain nothing more than rubble and gull guano, for only the sea birds have steady access to them.

And, of course, the ocean is closing in. On certain days at high tide, towers 5 and 6 are in the surf. One day they will fall into the sea, as the Cape Henlopen Lighthouse did in 1926.

Tower No. 10, on Cape Henlopen, is painted, maintained and used as a radar and ship reporting station. No. 8, behind the youth camping area of the park, is the one to be restored and opened to the public.

Tower No. 7, which rises behind the Great Dune south of the cape, is the only one currently open to the public. It has a steel, spiral stairway to the top. It overlooks the approximately 3,100 acres of pine forest, pond and beach that constitute Cape Henlopen State Park. It offers the best view of the joining of the ocean and bay, the blunt hook of the cape itself, and of the two rocky breakwaters in the mouth of the bay, with their distinctive lights.

From the tower's open platform you can see the hotels on the boardwalk at Rehoboth to the south, the town of Lewes to the north and the long pier built during the war to dock the tenders that strung the anti-submarine mines in the bay channel. Today the pier is jammed with fishermen. And you can watch the white Cape May-Lewes Ferry glide majestically between the two arms of land that embrace the entrance to the Delaware Bay.

Also from that height, you can better appreciate the apparatus of defense installed on the land below before the war, and the part the towers played in it.