Where is the largest national park in the European Union, and one of the largest national parks in the world?

Answer 1

French Guiana
Guiana Amazonian Park covers about 33,900 sq km (13,090 sq mi) of rain forest. In 20,300 sq km (7,840 sq mi) full protection is enforced and a further 13,600 sq km (5,250 sq mi) is under secondary protection.