Experience this reimagined and reawakened international landmark! This 1.5 hour tour involves astronomy, architecture, restoration, and human stories of the cosmic castle in the arboretum.
It requires climbing staircases and visiting small spaces thus is not wheelchair accessible. $46 for adults. Ages 10-18 are $24. Kids 9 and under are $7. This is our classic tour of the new and old Yerkes.
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For the adventurous who don't mind climbing winding staircases, ducking pipes, and exploring small spaces where astronomers work, this behind-the-scenes tour is your ticket!
This is not for kids under 15 or for anyone concerned with physical demands. Not wheelchair accessible. 1hr 45mins. $79 for adults. Kids ages 14-18 are $49. Friday mornings only.
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This tour is offered April-November. If there are no dates available when you attempt to purchase tickets, this is because all of our dates are sold out. If you are interested in being notified when our next round of tickets becomes available, sign up for notifications here.
With only 12 tickets available, this exclusive 2-hour experience illuminates the inner-workings of Yerkes after dark. During the tour, our Telescope Team will take you on a journey through the night sky with the largest refracting telescope in the world if skies are clear.
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Join us for one of our Open Houses! Each event has a unique theme and activities, making it an exciting, exploratory experience each time. Reservations are required. See below for the themes for the 2026 Open House season:
• Thursday, May 21: Exploring Art @ Yerkes
• Saturday, June 20: Summer Solstice Celebration
• Saturday, July 31, 2026: The Wonders of Physics
• Saturday, October 17, 2026: International Observe the Moon Night
Calling all K-12 educators! Join us this summer from 10am-1pm on Tuesday, July 14th or Tuesday, July 21st for a workshop focused on incorporating scaffolded, NGSS-inspired activities into your curriculum. Each program date will include the same content, as well as scaffolding and break-out groups for different age ranges.
Participants in this event will tour the observatory, learn how to facilitate and receive materials for a hands-on activity, and attend a lunch-and-learn session highlighting techniques for bringing science into your classroom. Classroom materials and lunch are included in the registration costs.
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Recent Poet Laureate of Wisconsin, Nicholas Gulig, comes for a discussion of his vibrant life, the PBS Wisconsin documentary Welcome Poets of which he's the subject, and a reading of some of his transformative poems on Thursday, June 4th at 6pm. We'll screen the film at no cost before the paid program. The film will be shown for free from 6pm to 7pm. The paid program with Nicholas will begin at 7pm. Adults 19 and over: $25. Youth 18 and under: $15. Welcome, Nicholas!
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SOLD OUT! We're over the moon to welcome Robin Wall Kimmerer on Thursday, June 18th at 6pm! The writer and scientist of international acclaim will be speaking about her wildly influential books, the wisdom of Indigenous knowledge, her Wisconsin ties, and more. Don't miss the MacArthur Fellow and National Humanities Medalist at Yerkes! All tickets are $50.
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Dr. Chanda Prescod-Weinstein describes herself scientifically as "a nonlinear combination of theoretical particle physicist, particle cosmology theorist, theoretical cosmologist, and particle astrophysicist." Get ready for one of the most engaging writers and thinkers on the planet on Thursday, June 25th at 6pm. Tickets are $37 for adults ages 19 and over, for youth ages 11 to 18, and for kids ages 5 to 10.
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We're excited to have Jeff Epping discuss his joyful life in garden design on Thursday, July 9th at 6pm. The nationally influential horticulturist will discuss his new book, The Gravel Garden: Visionary, Drought-Defying, Naturalistic Designs, followed by a signing. His brilliant work is showcased in Yerkes' arboretum, too! Adults 19 and over: $25. Youth 18 and under: $15
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We're thrilled to have Sue Breitkopf discussing America's most influential landscape designer Frederick Law Olmsted, his son John Charles who designed Yerkes' arboretum, and the largest concentration of Olmsted landscapes in Wisconsin around Geneva Lake in her talk "Olmsted Landscapes in Lake Geneva: Past Vision, Present Stewardship" on Thursday, July 16th at 6pm. Tickets are $37 for adults ages 19 and up, $23 for youth ages 11 to 18, and $130 if you want to bring kids ages 5 to 10.
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The world is wild about mushrooms, so we're having the celebrated botanist from the groundbreaking Pringle Laboratory, Dr. Anne Pringle, come to Yerkes to talk all things fungi. Her talk is titled "How Does a Lichen Grow? Asking the Wrong Questions and Discovering a Different Path to Immortality" on Friday, August 7th at 6pm. Tickets are $25 from adults ages 19 and up, $15 for ages 18 and under.
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The Astral Pastorales is a large-scale suite composed by Rob Mazurek and performed by his Exploding Star Orchestra. It unfolds as a celestial pastorale, an expansive sonic landscape where composition, improvisation, electronics, and spoken word merge into a single evolving field.
These shows are co-produced by Experimental Sound Studio and Instigation Festival. The eight musicians will be staying in Yerkes' restored, residency homes for the entire week. They'll be collaborating with Yerkes' astronomers, artists, and staff while immersing themselves in the culture of Yerkes, Williams Bay, and the Lake District. Yerkes staff members are pumped up for this fall celebration of music and cross-pollination in our special spaces.
These shows will be in the Big Dome at Yerkes on Friday, October 2nd at 7:30pm and Saturday, October 3rd at 7:30pm. Only 50 tickets are available per show! All tickets are $50.
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