Since the 1840s, there had been a series of stairways leading from the complex to the river level where tourists could descend and walk right next to the foot of the Horseshoe Falls, dubbed Behind The Sheet. These stairs were replaced in 1889 with a hydraulic lift, and by 1905, tunnels were cut inside the rock, establishing the forerunner of the Journey Behind the Falls attraction.

Davis' Table Rock House, standing since 1853, was in disrepair and was finally demolished in 1925 to make way for a new road and replacement building. Designed by the firm of Findlay and Foulis of Sault Ste. Marie, Ontario, this building is still in service today, albeit with major modifications since that time.

After World War II, the tunnels were relined with concrete and in 1951, an observation platform was constructed just north of the Horseshoe Falls. The attraction, now called the Scenic Tunnels, continued to draw increased tourist traffic; so much so that in 1963, extensive renovations were made to Table Rock House.

Modifications included the addition of the second floor observation plaza, and a planned "permanent" exhibit of replicas of the Royal Crown Jewels of Britain. This exhibit lasted until 1973 when, citing lack of visitors, it was removed. By this time, the Niagara Parkway was re-routed to the west end of the building, creating a pedestrian environment between Table Rock House and the Horseshoe Falls.

In 1974, the building known as Table Rock South or the annex, was constructed to expand retail space, including a second-floor, first-class restaurant. At first, the buildings were free-standing, but a massive reconstruction project in 1992-93 enclosed the area between the two buildings, while allowing for the complete renovation of the first-floor gift shop in the 1926 building.

The Scenic Tunnels attraction was renamed Journey Behind the Falls in the mid-1990s. Recently renamed Table Rock Center, the site continues to be a top draw for visitors and a top money-maker for the Niagara Parks Commission. The 2007 plan to renovate the area and increase its size was realized for the 2009 tourist season.

I have gone here almost every time I have gone to the Falls for many years and it never ceases to amaze. http://www.niagaraparks.com/attractions/behind-the-falls.html