Twitter's history in San Francisco as lit-up 'X' sign is installed at office Musk says company won't leave

On Market Street, San Francisco, there has stood a giant art-deco structure for 85 years. Well-known to the city's residents, it's the historic building where 'X' or 'Twitter' has been located for over a decade.

The building has been the source of much debate recently as the iconic Twitter logo has come down following the social media platform's rebranding, and the new lit-up 'X' sign has been erected.

And in addition to this, the company's CEO Elon Musk has said that while incentives have been offered to move out of the 'doom spiral' that is San Francisco, the company won't be moving anywhere.

He tweeted: "Many have offered rich incentives for X (fka Twitter) to move its HQ out of San Francisco.

"Moreover, the city is in a doom spiral with one company after another left or leaving. Therefore, they expect X will move too. We will not."

To understand why Musk is so intent on keeping Twitter grounded in San Francisco, you need to take a look back at the company's history.

In fact, Twitter was founded in San Francisco by Jack Dorsey, Noah Glass, Biz Stone, and Evan Williams in March 2006 before it was launched four months later.

The company decided to keep its roots in San Francisco while having more than 25 offices across the globe.

Six years after launching in 2012, the platform had more than 100 million users producing 340 million tweets a day.

Before the company was located in the building it is in today, there's a long history of how it got there.

At first, Twitter was located within the Obvious Corp offices - the company Twitter was originally born from. This was located on South Park Avenue and was home to Twitter in the days when folk were still working out exactly how it could be used.

By 2008, Twitter was located in its new building nearby on Bryant Street as it continued to grow in popularity.

But by mid-2009, Twitter moved out of this space and it was taken over by software company Xobni.

Twitter moved to Folsom Street where it leased a floor from retro platform Bebo. This allowed Twitter to triple its space in San Francisco.

But two and a half years later, Twitter was on the move again - for the last time - as it relocated to Market Street, Market Square, into a building formerly known as the Western Furniture Exchange and Merchandise Mart.

The building was built for a cost of $3 million in 1937 and took just one impressive year to complete.

It served as a large showroom for wholesalers and manufacturers of furniture, carpets, drapery, and other furnishings and appliances found in the home.

In its heyday, it was home to nine floors of showrooms - representing something like a DIY store's website today.

But by the 1990s, the Mart began to fade in importance and less and less wholesalers were still trading at the building. There were only 30 in 2008, while 300 remained in 2005.

The building was eventually converted into office space and bought in 2011 for $110 million by The Shorenstein Company.

As part of negotiations for tax breaks in San Francisco, Twitter was already engaged in negotiations for at least three floors of the converted office space in the old Mart.

1355 Market St became home to Twitter and today remains where X will have its main base.