Named for their shape, the 800-m (2,625-ft) wide and 50-m (164-ft) high Horseshoe Falls are formed by the turbulent waters of the Niagara River roaring over a semicircular cliff to plunge into the bubbling cauldron below. By these means the Niagara River adjusts to the differential between the water levels of lakes Erie and Ontario, which it connects. The falls remain an awe-inspiring sight, despite the fact that the flow of the river is regulated by hydroelectric companies, which siphon off a substantial part of the river to drive their turbines. One result has been a change in the rate of erosion. By the 1900s, the falls were eroding the cliff beneath them at a rate of 1 m (3 ft) a year. Today, the rate is down to 30 cm (1 ft) a year.

The best way to appreciate the full force of the falls is to experience the Maid of the Mist boat trip. Boats depart from the jetty at the bottom of Clifton Hill and head upriver to the crashing waters under the falls. Raincoats are provided on this invigorating and wet trip.

This short, steep street runs up from the edge of the Niagara River gorge and is lined with a string of fast food restaurants and gaudy tourist attractions. The flashing lights and giant advertising billboards point the way to such sights as the Guinness Book of World Records, House of Frankenstein, That’s Incredible Museum, Houdini’s Museum and Ripley’s Believe it or Not! Museum, where visitors can speak to a genie in a crystal bottle and see oddities such as a man with a greater-than-usual number of pupils in his eyes.

The great force of the Niagara River’s torrent is best admired from down at the bottom of the canyon. The Great Gorge Adventure provides this close-up view by means of an elevator and a tunnel, which lead from the top of the gorge to a riverside boardwalk. The whirlpools and rapids here are some of the most spectacular, yet treacherous, in the world.

Just above the falls, stranded on the rocks in the middle of the river, is the Old Scow, a flat-bottomed barge that was shipwrecked in August 1918. It was being towed across the Niagara River by a tugboat when the lines snapped. The scow hurtled towards the falls, getting within 750 m (2,460 ft), of the brink, and the two-man crew appeared to be doomed. Luckily the boat grounded itself on this rocky ledge just in time. The crew’s ordeal was, however, far from over: they had to wait another 29 hours before being finally winched to safety. The Old Scow has been rusting away on the rocks ever since.

The small Niagara Glen Nature Reserve lies 7 km (4 miles) downriver from the falls. This segment of the gorge has been preserved in pristine condition, with bushes and low trees tumbling down the rocky cliffside. This is how it may have looked before the coming of the Europeans. Seven different hiking trails lead past boulders, caves, and wild flowers. The walks are easy on the way down but a steep climb on the way up.

The Niagara River makes a dramatically sharp turn about 4.5 km (3 miles) downstream from the falls, generating a vicious raging whirlpool, one of the most lethal stretches of water in the whole of North America. The effect is created when the river pushes against the northwest side of the canyon, only to be forced to turn around in the opposite direction. The most stunning view of the whirlpool rapids is from the Spanish Aerocar, a specially designed cable car that crosses the gorge high above the river. A different perspective of the falls can be seen from here.

The Niagara Parks Botanical Gardens are located 9 km (6 miles) downstream from the falls and comprise over 40 ha (99 acres) of beautifully maintained gardens divided into several different zones. One of the prettiest areas in summer is the rose garden, which displays over 2,000 different varieties. The extensive annual garden, which houses many rare species imported from all parts of the globe, puts on a year-round show. The gardens also include an arboretum that has examples of many different types of trees from beech and mulberry to magnolia and yew.

The butterfly conservatory is even more popular. At the beginning of a visit, a video is shown in the theater. The film explains the life cycle of a butterfly, from egg and larvae through to the emergence of the adult. Several thousand butterflies are housed in a huge heated dome where they fly free – one of the largest collections in the world. A series of pathways pass through the dome, leading past the lush tropical flora on which the butterflies make their homes.