Remember the old nursery rhyme "London Bridge Is Falling Down"? Well, it was. In 1968, after about 150 years of constant use, the 294-foot-long landmark was sinking into the Thames. When Lake Havasu City founder Robert McCullough heard about this predicament, he set about buying London Bridge, having it disassembled, shipped more than 5,000 miles to northwestern Arizona, and rebuilt, stone by stone. The bridge was reconstructed on mounds of sand and took three years to complete. When it was finished, a mile-long channel was dredged under the bridge and water was diverted from Lake Havasu through the Bridgewater Channel. Today, the entire city is centered on this unusual attraction. Walking tours are offered Tuesday, Thursday, and Saturday at 11 am from October through April; the cost is $10 per person, and reservations are required. These guided strolls leave from the Lake Havasu City Visitor Center at the east base of the bridge, where you'll find a colorful re-creation of an English Village that houses a few curio shops and restaurants and offers good views of the channel of cool blue water flowing under London Bridge. On the west side, you'll find a handful of more urbane restaurants as well as the hip Heat Hotel.