These are some of the extreme places I’ve been to:

Northernmost: Kemijärvi, Finland, 66° 43′ N
Southernmost: Ushuaia, Argentina, 54° 48′ S

Highest: El Misti, Peru, 5822m above sea level
Lowest: Dead Sea, Jordan, 410m below sea level

Hottest: Beijing, China, 40°C
Coldest: Stockholm, Sweden and Vilnius, Lithuania, both -17°C.