Chinese President Xi Jinping is visiting Spain en route to the G20 summit in Buenos Aires. His stop in Madrid comes as China and Spain mark 45 years of diplomatic ties. In recent years, trade has increased. Chinese investment in Spain is up, and there are more Chinese visitors to Spain than ever. CGTN's Al Goodman reports from Madrid.

It wasn't always like this -- large groups of Chinese tourists in Madrid. Ready to explore, in the heart of the Spanish capital. Yet when China and Spain started diplomatic relations 45 years ago, there were hardly scenes like this. But that was long-ago history for both countries, says this economics professor.

GONZALO GARLAND PROFESSOR OF ECONOMICS, IE UNIVERSITY "Things have changed dramatically, in all this period, and clearly the relationship between both countries has also become a lot more intense."

Chinese President Xi Jinping will get a feel for that intensity on a visit to Spain this week. He'll meet Spanish King Felipe the Sixth and Prime Minister Pedro Sanchez. President Xi's visit comes as the Chinese Embassy is upgrading and adding new facilities. And as the two nations have strengthened economic ties in recent years.

AL GOODMAN MADRID "Trade and investment have increased between China and Spain. But Spain is importing a lot more from China and exporting much less. So Spain has a $21 billion dollar trade deficit with China."

This former Spanish ambassador to Beijing, now a business executive, says China's key global development strategy will surely be discussed in Madrid.

JOSE-PEDRO SEBASTIAN DE ERICE SECRETARY GENERAL, TECNICAS REUNIDAS "We think the Chinese companies and the Chinese government is allocating a lot of money for these projects, called OBOR, One Belt and One Road."

His firm has designed and built 26 oil, gas and chemical plants in China over the years. While China focuses on its development concept, some Chinese have invested in Spanish football. Like the Wanda conglomerate. Its name is on Atletico's Madrid's stadium. While Chinese tourism to Spain has dramatically increased in recent years, now around 700,000 visitors annually. This executive at Spain's largest hotel company, which also has hotels in China, says they've trained their staff to accommodate Chinese visitors.

BERNARDO CABOT SENIOR VP FOR ASIA PACIFIC, MELIA HOTELS "All of them, they know how important is the food, the welcome, the language, the payment methods, how they book, what they want, and this is something that our company invested in the last years, in order to welcome the Chinese traveller."

And now, as the highest delegation of Chinese travelers is about to visit Madrid, Spanish officials hope they'll display the right kind of welcome. Al Goodman, CGTN, Madrid.