When Blenheim Palace held an exhibition by dissident Chinese artist Ai Weiwei, it had the desired effect of attracting different types people compared to those who usually visit the historic site.

Blenheim Palace chief executive John Hoy said: “That brought a whole new audience for us. International visitors were attracted by an international art show.”

The palace’s success with the Ai Weiwei exhibition, which ran from October 2014 to April 2015 and helped boost attendances, is indicative of a wider trend of tourist attractions in and around Oxford enticing foreign visitors.

According to an Office for National Statistics (ONS) report released last week Oxford was the fourth-highest city in the UK in terms of spending by overseas tourists in 2014, taking in £325m for the year (London came first with £11.8 billion).

Mr Hoy said that total visitor numbers for Blenheim Palace, which is located just outside Oxford in Woodstock, were up five per cent to about 640,000 in 2014 compared to the previous year. This was in line with the increase in international tourists to the UK over the same period.

He estimates about 20 per cent of visitors to the World Heritage site are foreign and the remaining 80 per cent domestic.

“Blenheim draws people from pretty much everywhere,” he said. The top two countries, however, are North America, because of the palace’s connection with Winston Churchill, and China.

The palace is intent on continuing to build its international audience. This year, his birthplace Blenheim is commemorating the 50th anniversary of his death. In 2016, it will celebrate the 300th anniversary of the birth of landscape architect Capability Brown, who designed the palace’s extensive grounds.

There will also be more art exhibitions. “The aim is to have a strong contemporary art show each year,” said Mr Hoy.

“Oxford and Oxfordshire have a lot to offer. We’ve got a real mixture of things.”

The 18th-century palace, Oxford’s historic colleges, the medieval Oxford Castle, the Bicester Village retail outlet and a host of other attractions remain high on the list of destinations for foreigners.

The ONS report found that Oxford recorded the seventh-highest number of foreign visitors in 2014 among UK cities, attracting 490,000 international travellers over 3.4m nights. International tourists spent an average £662 over the duration of their visit to Oxford, or £95 per day.

Europeans were the biggest group to Oxford, making 303,000 visits last year, followed by tourists from other countries at 116,000 and North Americans at 71,000 visits.

The biggest single age group travelling to Oxford was 45 to 54-year-olds, who made 96,000 visits in 2014.

The most common reason for visiting Oxford was holidays (39 per cent of all foreign tourists), followed by visiting friends or relatives (27 per cent), business (24 per cent) and other (10 per cent).

Theresa Nicolson, marketing manager of the Ashmolean Museum, said the Oxford cultural institution’s biggest groups of foreign visitors were from North America and China.

“We [also] see a lot of school groups and team groups: Chinese, Spanish, French.”

Mrs Nicolson said a recent exit survey revealed that about 13 per cent of the museum’s total visitors were from abroad.

However, during peak summer periods the number of foreigners could be as high as one in every five visitors.The Ashmolean attracts about 850,000 people a year.

She said: “As we have such a wonderful wealth of art and history on offer here with world class collections that span the globe and all of this can be seen for free, I think many foreign visitors like to simply enjoy our permanent collection.

“We have some really exciting exhibitions coming up next year, including an Andy Warhol show and a brilliant marine archaeology exhibition focusing on amazing artefacts found in the sea round Sicily, and it will be interesting to see if we attract more foreign visitors to those.”

Jamie Craig, curator of the Cotswold Wildlife Park, said the park was also benefiting from the rise in international tourists.

He said: “We do get a lot of foreign families visiting.”

Mr Craig said visitors rose six per cent to 344,833 in 2014. “It’s a decent rise for us.”

He said foreign families generally arrived at the wildlife park, which is located about 20 miles west of Oxford, by car, rather than on tour buses.

“You come here and it feels like old-fashioned English,” he said.