Research suggests Banksy's show has a national appeal
Banksy's exhibition at Bristol Museum and Art Gallery has been an "absolutely extraordinary success" for the city.
John Hallett, Managing Director of Destination Bristol, says it has drawn visitors from across the UK.
"We're working very hard with the museum now to try and put some hard figures on this because people want to know how much it's worth."
The exhibition, which opened shrouded in secrecy, has already seen 120,000 people visit.
Mr Hallett added that their current research shows the exhibition has a wide national appeal.
"We've got a lot of anecdotal evidence now from speaking to people who are going to the show, finding out where they're coming from.
"We're finding people travelling literally the length of the country just for the day and then going back home to Scotland because they want to see this exhibition."
I think if people have got value for money they will come to a city
Neil James, Bristol Marriott hotel
He added that although firm figures over the impact of the exhibition on local businesses was not yet available, interim figures could be released in the "next few weeks".
A straw poll carried out by BBC Bristol showed that many nearby hotels were reporting an increase in bookings.
One nearby restaurant also reported a 24% increase in trade.
Neil James from the Bristol Marriott hotel said: "I think people are definitely looking for something different to do and Banksy coming to Bristol has had a definite effect.
"We saw an increase in occupancy on a later scale in terms of people booking much later when it was first announced.
"I think if people have got value for money they will come to a city," he added.
But Mr Hallett from Destination Bristol warned that Bristol would need to find another tourist draw for the coming years to keep up the momentum left by Banksy.
"This was a major, major coup for the city and the museum. It was fantastic news. It's got so much media coverage - we need something like this every year.
"I don't know where the next one is going to come from but this has been a spectacular success."
Banksy v Bristol Museum is on at the City Museum and Art Gallery until 31 August 2009.
It is open seven days a week and entry is free.