One of Victoria's oldest tourist attractions has closed down after nearly 50 years of operation, but at least one tourism expert says that's not necessarily a bad thing.

The Pacific Undersea Gardens was first opened in Oak Bay in 1964, and has been a fixture in the city's Inner Harbour since moving to its current location in front of the provincial legislature in 1969.

The 150-foot-long floating aquarium allowed visitors to descend below the ocean's surface to view West Coast sea life in the many tanks and displays.

This morning its doors will not open to the public, but Tourism Victoria board member Deirdre Campbell says that's not necessarily bad news.

"The Inner Harbour is obviously a big focus for tourism in Victoria and we have found that there is a desire to change, to take that Inner Harbour to a new level."

"The Undersea Gardens is old, it's dated. Time to either change it, invest a lot of money or close it down," said Campbell.

Its operators, The Oak Bay Marine Group, lease the waterlot from the Provincial Capital Commission, but the group has not yet revealed its plan for the site.

PCC CEOO Rick Crosby says the Oak Bay Marine Group could sublet the space until 2017, or convert it into another permitted use.               

Crosby says a small marina is the most obvious choice and could be ready by next May when the tourism season begins, but it would require city approval.

"The future use of the water lot would be guided by city zoning," says Crosby.

With files from the CBC's Lisa Cordasco