NARCISSE, Manitoba — Tokyo has its cherry blossoms, the Netherlands has its tulip fields, and Paris offers itself. But the Canadian province of Manitoba has a remarkably distinct springtime attraction too: tens of thousands of amorous snakes writhing around in pits.

While Manitoba’s tourist agency doesn’t promote the Narcisse Snake Dens with the same zeal as it does Canada’s national human rights museum in Winnipeg, the annual mating ritual of red sided garter snakes nevertheless manages to draw thousands of people — snake fanciers and snakephobes alike — to an otherwise overlooked part of the province for a few days each spring.

The area around Narcisse is so attractive to snakes for the same reasons many farmers abandoned it decades ago: Its thin topsoil sits on top of limestone that water has gradually eroded underground, creating a network of small caves that can be entered through sinkholes.