A riverfront that was once choked with factories has been transformed into vibrant parks and trails busy with walkers, joggers and bicyclists. A munitions plant is located on an island in the Mississippi River where an Iowa city's namesake was murdered. A company known for its hard-working machines doubles as a theme park for visitors. A region not known as a favored destination for foodies has a lively craft brewing scene. The region known as the Quad Cities is full of surprises.

Even the nickname is a surprise. "Quad" usually means four, but the area's 400,000 residents live in five major cities: Davenport and Bettendorf in Iowa and Rock Island, Moline and East Moline in Illinois. "Quint Cities" never got traction.

Like St. Louis, the history of the Quad Cities is intricately linked to the Mississippi River. Before the lock and dam system was built in the 1930s, this stretch of the river was notorious for its dangerous rapids; steamboats needed a pilot with specialized expertise to navigate them. Villages developed around this natural way station, which eventually grew into manufacturing and commercial centers. A visit to the region should therefore begin at the river.

THE RIVER

In most places, the Mississippi River runs from north to south, but through the Quad Cities, it runs east to west. A bike ride on a riverfront trail can help you get oriented. In Iowa, the Davenport Riverfront Trail runs five miles from Credit Island to the Isle of Capri Casino in Bettendorf. If you begin at Credit Island Park, you can snap photos of yourself with the quirky, life-size figures that artist Thomas Gleich sculpted; they are based on the painting "A Sunday on La Grande Jatte" by Georges Seurat. On the Illinois side, the Mississippi River Trail begins at Sunset Park in Rock Island; if you feel ambitious, you can ride it all the way to Savanna, which is 65 miles upriver.

For a two-state ride, you can bike across the Mississippi River on either the Centennial Bridge or Government Bridge (both connect downtown Davenport to downtown Rock Island). Further upstream, you can use the Channel Cat Water Taxi to cross the river, which has riverfront stops at Moline, Bettendorf and East Davenport. The water taxi is a fun ride in its own right — riding the complete loop takes about an hour — and you can bring your bicycle on board, as long as the boat isn't full.

ARSENAL ISLAND

Col. George Davenport, from whom the town gets its name, was one of the first European settlers in the region. Davenport, born in 1783 in England, served with the U.S. Army during the War of 1812. After his discharge, he set up Fort Campbell's commissary on Arsenal Island. Davenport's home served as a focal point for the small but growing communities nearby. In his house, Rock Islanders hatched a plot to win the county seat, and railroad executives were courted.

He was shot and mortally wounded by burglars in his home on Independence Day, 1845. A massive manhunt resulted in the capture and conviction of six men, three of whom were hanged in front of a large and boisterous crowd just three months after the murder. The Federal-style house where Davenport died has been restored to its 1830s appearance and is now a museum.

Arsenal Island was acquired by the U.S. government in 1804 via a treaty whose legitimacy was disputed for three decades by local Sauk and Meskwaki Indians. The government showed little interest in the island until the Civil War. After the armory at Harpers Ferry, Va., was bombed in 1861, opportunistic politicians lobbied successfully for a new armory on Arsenal Island. Over time, the site developed into a major weapons manufacturing installation, primarily for small arms and supplies such as mess kits.

The island today has several attractions that are worth a visit. Keep in mind that, although you are welcome to tour the island, it is military property and you will need to stop at security and show a picture ID before you can enter. (And you may not ride a bicycle onto the island.)

The Rock Island Arsenal Museum, founded in 1905, has an impressive collection of handguns, rifles and other small arms. Somewhat larger weapons are on display at Memorial Field; walk around and touch artillery and rocket launchers, most manufactured on-site. Elsewhere on the island, you will find two national cemeteries, including one for the 2,000 Confederate soldiers who died while imprisoned on the island during the Civil War.

THE JOHN DEERE EXPERIENCE

The Quad Cities region was a manufacturing powerhouse for a century. Their proximity to the fertile plains of the Midwest ensured that much of their manufacturing energy would be spent producing farm implements. International Harvester, Case, Caterpillar and, of course, John Deere, all had large factories. Although many of those factories are now gone, John Deere still has a dominating presence, especially in Moline. You can learn more about the company and its products at John Deere Pavilion in downtown Moline. Kids of all ages will get a thrill from making the steep ascent into the cab of a 9970 Cotton Picker or one of the many other tractors you are welcome to climb aboard.

If you visit during the week, you can also tour Harvester Works, the 25-acre factory where John Deere combines are manufactured. The 90-minute tour is great fun, especially if you are fascinated by how things are made. Visitors see nearly every step in the production process, from fabricating sheet metal to painting to installing the high tech cab.

When the company needed a new headquarters building in 1956, they turned to Eero Saarinen, the visionary designer of the Gateway Arch. Saarinen designed a three-building campus in a wooded setting, opting to cover the buildings with Cor-Ten steel, a material that was originally developed for railroad tracks. Over time, Cor-Ten develops a coating of iron oxide, which helps to resist rusting. The campus is just 10 minutes from downtown Moline; the main building has a visitor center on the first floor that showcases more John Deere products.

CRAFT BEER

The area has three outstanding brewpubs, each serving up distinctive flavors in brews, food and atmosphere. In Davenport, the Front Street Brewery is housed in a 19th century commercial building in the former red light district known as Bucktown. The food leans toward upscale pubgrub but includes a number of sandwiches and wraps, too. The English ale-inspired Raging River Ale is their signature beer.

The Blue Cat Brewery in downtown Rock Island is a vibrant brewpub with the friendliest regulars in town. The menu includes creative comfort food such as sirloin steak chili and meatloaf served with seared spinach. On the beer side, the medium-bodied Off the Rail Ale is a popular choice, but don't shy away from the seasonal beers, which may include a fruity option like the cranberry ale or a serious one like the Count Magnus Belgium Strong.

At Bent River Brewing Co. in downtown Moline, 10 gleaming copper kettles run along a wall behind the bar. From those kettles comes the widest range of beer available in the region, with eight to 10 beers on tap at all times. My personal favorite is the Uncommon Stout, a medium-bodied beer with more than a hint of coffee. The menu includes mostly hearty pub entrées like shepherd's pie, fish and chips, and burgers. Local and regional bands keep the place popping on weekend nights.

Dean Klinkenberg is the St. Louis-based author of "The Mississippi Valley Traveler" guide book series.