A US$22m (€19.8m, £16.9m) "Treetop Trail" built on a former monorail track, a nature-based preschool, and camping facilities are among reported changes that Minnesota Zoo in Apple Valley, US, is considering.

The Minneapolis-based Star Tribune newspaper reports that the plans have been developed and presented to the board by director and president John Frawley, who joined the zoo in 2016. They are notable for their focus on outdoor pursuits as a means to attract visitors, rather than new or exotic animal exhibits.

Key parts of the project include the aforementioned Treetop Trail, which the report says at 1.3 miles long would likely be the longest elevated trail loop in the US, a rock-climbing facility within a vacant IMAX theatre, paved trails, a lodge and several camping options.

"The Treetop Trail is what's got everybody buzzing," Charlene Briner, vice chairwoman of the zoo board, is quoted as saying. "They like the idea that we are redeploying and modernising an asset that is right now unused."

Animal "encounters" could be manufactured in new areas, such as by organising hikes out to visit an elk herd, or by zookeepers bringing certain animals to campsites or the Treetop Trail.

Overall the facilities plan aims to make the zoo easier to navigate; it will also renovate ageing elements – such as an animal hospital – and fix infrastructures such as bridges, roads and roofs.

The zoo, which typically receives about a third of its budget from the state, is seeking US$39m (€35.1m, £29.9m) from the legislature in 2020, including US$11m (€9.9m, £8.45m) for the Treetop Trail, US$15.5m (€13.95m, £11.9m) for revitalisation projects, and US$12.5m (€11.25m, £9.6m) for repairs and updates.

Ms Briner added that the plans did not mean that the zoo's identity and focus on animals would necessarily change, saying: "We don't want to become like a nature amusement park."

The zoo said the plans actually align with its longtime mission, which is to "connect people, animals and the natural world to save wildlife".