After the massive success of rooftop and elevated parks like the Promenade Plantée in Paris or the famous High Line in New York City, developers are scrambling to transform other urban spaces into green getaways for the public. The latest innovation in parks is the bold Lowline project in New York City, a proposed underground park that would be the first of its kind anywhere in the world. If the plan comes to fruition, the Lowline will fill an abandoned trolley terminal on the city’s Lower East Side with open space and greenery—there’s just one little problem. Co-founders James Ramsey and Dan Barasch need to find a way to get sunlight into the underground park, so they launched a successful Kickstarter campaign that will fund a “Lowline Lab” for testing solar technology. The  Lowline team still needs city approval and hundreds of thousands of dollars to make their project a reality, but even in its earliest stages, the park is a glimmer of hope in the concrete jungle. While you wait to stretch your legs in the Lowline, take a look at some other unique parks around the world.

Mill Ends Park (Portland, Oregon)

Don’t count on laying your picnic blanket here—this park is only two feet long! With a total area of 452 square inches, Mill Ends Park is certified by the Guinness Book of Records as the smallest park in the world. Created in 1948 when a lamppost intended for the site never appeared, the tiny park has played host to everything from a swimming pool for butterflies to a miniature Ferris wheel. It was named an official city park in 1976, and  today it’s the site of many of Portland’s St. Patrick’s Day festivities.

Garden of Cosmic Speculation (Dumfries, Scotland)

For a walk in the park as enriching as it is refreshing, head across the ocean to experience the awe-inspiring Garden of Cosmic Speculation. Located in South West Scotland, the park and sculpture garden is a 30-acre spectacle designed by theorist and landscape architect Charles Jencks. The garden may be predominantly devoid of foliage, but it’s full of sculptures and landscaping inspired by mathematics, science, and cosmology. According to Jencks’ website, “a water cascade of steps recounts the story of the universe, a terrace shows the distortion of space and time caused by a black hole, a ‘Quark Walk’ takes the visitor on a journey to the smallest building blocks of matter, and a series of landforms and lakes recall fractal geometry.” However, visitors are advised to plan their trip wisely—the garden is only open to the public one day a year.

Jardin Botanique de Montréal (Québec, Canada)

190 acres and numerous collections and facilities make the Montréal Botanical Garden one of the most highly regarded botanical gardens in the world. Visitors can explore one of four main sections: a Chinese garden with an artificial mountain and a collection of donated bonsai and penjing; a Japanese garden featuring tea ceremonies and a large koi pond; the First Nations Garden dedicated to the indigenous Canadian population; and the Alpine Garden covered in small alpine plants. Other attractions include a poisonous plant garden and an arboretum.

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