Love or hate them, zoos make up part of the geography of many cities. And some of the programs they offer outside their daytime opening hours these days are rather wild.

• Amsterdam’s Artis Zoo, celebrating its 175th anniversary, offers a program called “ZOOmeravonden,” or “Summer Nights at the Zoo,” every Saturday night through August, when the zoo remains open until sundown. Younger visitors will enjoy face-painting and scavenger hunts while the older generation takes in a concert. Learning from the zookeepers what the animals get up to at night or visiting the planetarium promises fun for all visitors. See details at http://tinyurl.com/o6pepao.

• The Erlebnis-Zoo Hannover will offer a “Canadian Evening” in the theme area known as Yukon Bay on Aug. 30. Entertainment harks back to the era of the gold rush, and includes polar bear feeding, a seal show, line and can-can dancing, lasso demonstrations, bull riding, panning for gold, horseshoes, a barbeque and more. Adult entry including food, drinks and entertainment costs 79.50 euros (about $103); ages 3-17 pay 35.50 euros. Get details at http://tinyurl.com/oj39cbz.