Below are the countries I visited before 2018:
(“visited” means I spent meaningful time outside of a transportation hub [such as an airport or train/bus station], and went to at least one place of interest, such as a tourist site or restaurant):
Australia Kenya
Austria Korea (South)
The Bahamas Malaysia
Belize Maldives
Cambodia Malta
Canada Mexico
Chile Monaco
China Mongolia
Costa Rica Nepal
Croatia New Zealand
Dominica Nigeria
Dominican Republic Philippines
Fiji Portugal
Finland Russia
France Saint Lucia
Germany Singapore
Guatemala Slovenia
Haiti Spain
Holy See (Vatican City) Sri Lanka
Iceland Switzerland
India Thailand
Indonesia Taiwan
Italy United Arab Emirates
Jamaica United Kingdom
Japan United States
Jordan Vietnam
52 Countries Total