WARSAW, Poland (AP) — Danish Crown Prince Frederik and Crown Princess Mary are marking 100 years of Denmark’s diplomatic ties with Poland with a one-day visit to Warsaw that involves meeting Poland’s president and World War II veterans.

Frederik and Mary were greeted with military honors Monday by Polish President Andrzej Duda in front of the Presidential Palace.

Later in the day, they are set to open a conference at Warsaw University on the history of the countries’ ties.

They are also due at the nearby Polish Academy of Sciences to dedicate a memorial plaque to Danish 19th-century sculptor Bertel Thorvaldsen, who made monuments in Warsaw to Polish astronomer Nicolaus Copernicus.

Talks in coal-reliant Poland will also include climate protection and a joint gas pipeline project.