But Scottish Gas Networks is now considering their future after the towers were decommissioned as part of a major redevelopment of the site.
The two blue towers can each hold 283,000 cubic metres of gas. They are each 280ft in diameter and among the largest of their kind in the UK.
Earlier this year, Scotland Gas Networks was given permission to develop the site at Blochairn Road.
Now the company has lodged a new application for permission to store up to 500 tonnes of gas in mobile tankers at the East End site.
A Scottish Gas Networks spokeswoman said: "Scotland Gas Networks put in a planning application to develop the existing infrastructure at our Provan site.
"This application has been approved.
"We are building a parking area for some of our Liquified Natural Gas (LNG) tankers.
"The amount of gas on the site at any time will not exceed the amount stored at the site previously in the gas holders.
"The gas holders at Provan are not used for storing gas any more. As with all industries, technology has developed and we no longer need to use this means of storage.
"We will be considering the future of these gas holders but no decisions have been made."
Provan Gas Works was built by Glasgow Corporation in 1904.
The site later became part of British Gas and, subsequently, Scottish Gas Networks.
Originally the plant undertook gas manufacturing from the coking of coal, but was downgraded significantly in the 1980s.
Most recently, the plant was used solely for gas storage and distribution.
Since the construction of the M8 and M80 in the 1970s and 1980s, which run directly next to the plant, the twin gas holders have become an unofficial symbol for those driving from Edinburgh and the north that they have almost reached Glasgow city centre.
The towers have also gained an affection among Glaswegians since they were used to display huge placards promoting the "Glasgow's Miles Better" campaign.
A Glasgow City Council spokesman said: "The application will be considered in due course."