Can't say we're surprised.

MasterCard has just released its annual travel study, the Global Destination Cities Index, ranking 132 destination cities around the world in terms of total international overnight visitor arrivals and cross-border spending.

London came first in the study for the second year in a row.

Bangkok lost its first place ranking in 2013, largely due to political unrest.

But the report suggests that the Thai capital is showing signs of recovery and closing the gap with London.

London will welcome 18.82 million overnight visitors in 2015 whereas Bangkok will receive 18.24 million.

Not only will London have the most travelers, it's estimated to see the most visitor spending, at $20.23 billion in 2015.

New York came second in visitor spending at $17.37 billion.

Paris followed with $16.61 billion.

London and Bangkok have taken the top two spots in the MasterCard Global Destination Cities Index for the last five years.

"This is an impressive achievement and it is similar qualities that have kept them both at the top," said Eric Schneider, group head of MasterCard Advisors, Asia-Pacific.

"Despite their size, they are both relatively easy to navigate for a tourist, and even in Bangkok, English is often all you need to get around.

"Food and culture are also available in abundance.

"Finally, it's the unique and seemingly limitless heritage, from temples to palaces in Bangkok or churches and castles in London, that keep enticing tourists to make the trip."

Asia dominates, but lacks diversity

The ranking is heavily tilted toward Asia.

"Against a background of generally weak global economic growth and anemic pace of exports, a vibrant tourism sector is providing a powerful boost to income and job creation in Asia-Pacific," said Dr. Yuwa Hedrick-Wong, chief economist and chair of the Academic Advisory Council at the MasterCard Center.

The report points out a lack of diversity in the source of tourism arrivals for some Asian cities.

The top five visitor groups coming to Bangkok, Singapore and Kuala Lumpur, Malaysia, for example, are all from the Asia-Pacific region.

Istanbul has the most diverse visitors, with half of its inbound tourists coming from 33 different countries.

Diversifying sources of visitors means a higher resilience against long term economic instability, according to the report.

World's fastest growing cities are ...

Among the 10 fastest growing cities in the world (based on data gathered over the last six years), seven are in Asia.

Sri Lanka 's capital city of Colombo is first in growth with a staggering 21% surge, with Chengdu , the capital of China's Sichuan province, following in second.

Abu Dhabi , capital of the United Arab Emirates, ranked third in terms of growth; Riyadh, Saudi Arabia, placed fifth.

Lima , Peru, is the wold's ninth-fastest growing city, and the fastest growing city in South America.

Houston is the fastest growing city in North America since 2009 and is the only city in the United States to register double-digit growth over that period.

Top 10 destination cities for 2015 (by projected visitor arrivals)

1. London 18.82 million

2. Bangkok 18.24 million

3. Paris 16.06 million

4. Dubai, UAE 14.26 million

5. Istanbul 12.56 million

6. New York 12.27 million

7. Singapore 11.88 million

8. Kuala Lumpur, Malaysia 11.12 million

9. Seoul 10.35 million

10. Hong Kong 8.66 million

Top 10 cities for international overnight visitor spend for 2015

1 London $20.23 billion

2 New York $17.37 billion

3 Paris $16.61 billion

4 Seoul $15.24 billion

5 Singapore $14.65 billion

6 Barcelona, Spain $13.86 billion

7 Bangkok $12.36 billion

8 Kuala Lumpur, Malaysia $12.02 billion

9 Dubai, UAE $11.68 billion

10 Istanbul $9.37 billion

Fastest growing tourist cities

1. Colombo, Sri Lanka 21.1%

2. Chengdu, China 20.7%

3. Abu Dhabi, UAE 20.4%

4. Osaka, Japan 19.8%

5. Riyadh, Saudi Arabia 18.0%

6. Xi An, China 16.2%

7. Taipei, Taiwan 14.9%

8. Tokyo 14.6%

9. Lima, Peru 13.9%