EVERETT — What’s 50 feet long, floats and is green and yellow all over?

Swimmers at the Forest Park pool will find out at the 6 p.m. open swim session tonight.

For the first time, the city plans to let the public try out its newest toy, an inflatable obstacle course.

Pool staff plan to blow it up for Friday night swim sessions and private birthday parties.

“It’s a nice amenity,” said Marianne Pugsley, who oversees operations at the Forest Park Swim Center.

Swimmers start at one end and negotiate a serious of obstacles that include a slide, a gaping hole called a pond and a sheer face they have to shimmy across. The toy is designed so two people can race each other across.

Lifeguards plan to manage the flow of people to keep play safe, she said.

Earlier this week, the pool staff broke the new toy out of its box and inflated it for the first time. High school girls showing up for swim practice made a beeline for the toy and were soon scampering across it.

Some of their parents were discussing whether they could get away with trying it out in their street clothes.

The toy is a replacement for another inflatable the pool has used for four years, Pugsley said. That toy proved extremely popular — and not just with children.

“The dads are hysterical,” she said. “It brings out the kid in everybody.”

The other inflatable toy wore out and the pool staff had problems with air leaks. They expect this toy, produced by a different company in Germany called Wibit, will be more durable. The toy cost $8,000 and has a 10-year life span.

Public pools across the region are investing in amenities to draw customers. For instance, plans for the new Lynnwood pool under construction include water slides and whirlpools.

“It’s the trend in the industry to make your pool a destination,” Pugsley said.

The obstacle course is a cost-effective way for the city to offer customers something fun without a remodel, she said.

Debra Smith: 425-339-3197, dsmith@heraldnet.com.