Given the increasing popularity of mountain bike riding over the past decade, it's hardly surprising it is featured in the latest Destination Wollongong tourism video.

The proximity of the escarpment with its myriad steep trails makes Wollongong an ideal location for mountain biking.

However, as the vast majority of those trails are on private or state-owned land, mountain bikers in the Illawarra are more often than not breaking the law in pursuit of their chosen sport.

One popular location for mountain biking is the former Excelsior No 2 mine at Thirroul. The land is owned by non-profit company Big Fat Smile, which recently replaced the site's faded and obscured warning signs in an attempt to deter further riding.

Chief executive Bill Feld said mountain bikers and others were using the land, particularly the steep sections, without authority.

"The signs are there to deter entry to private property. [They] say 'Do Not Enter' and that's our wish," he said.

The new signs have not deterred riders from using the site.

Kyle Clinton, from Corrimal, regularly rides at the site and although admitting he was "technically trespassing", felt local mountain bikers had been left with little choice.

"It's a joke," he said.

"We're out here doing something that doesn't cause anyone any trouble, where are we supposed to go?"

Steve Locke drives down from Sydney to ride at Excelsior and said the danger was minimal, particularly as older riders were using the site.

"We older guys spend time making the trails safer. We take pride in maintaining the area, and understand we only get back from it what we choose to put in," Mr Locke said.

Dan Johnstone travels down with Mr Locke and could not believe Wollongong had not taken advantage of the escarpment to attract more mountain bikers.

"The escarpment is a blank canvas," he said. "It's perfect for mountain bikers and if a proper facility was given the green light, it would attract a huge amount of riders, not just locally, but from around the world."

Wollongong council has recognised the need for such a facility, and one proposal under consideration is the construction of a mountain bike facility at Mount Keira.

Real Estate agent Michael Moate, a keen mountain biker, believes a proper facility would be fantastic for the region.

"It's a great idea," he said. "Not only will it be safer for the riders, it will also be extremely beneficial to the local economy."