They claim to still have the world's largest refracting telescope, weighing 6 tons with a 40-inch diameter lens (others have claimed it's the largest working refractor, and a larger one of 50 inches exists in France, but not currently operational). It's quite a thing to behold in person. Given the space constraints, it proved difficult to get into a single photograph. Another person on the tour and I tried to calculate its magnification and it came out to something like 497.33, which was smaller than we both thought. Or we both calculated it incorrectly the same way independently, which remains another possibility. Though huge, it's still an old telescope and definitely now behind the times.
The floor of the large observatory also raised and lowered by motor, so we rose slowly upwards to see the telescope up close. This allowed a better look at the eye piece and the immense finder scope (I will probably never own a telescope as large as that finder scope).
Though a little off the main highways, the building itself and its history proved well worth the extra drive time. Even people who don't have an interest in astronomy would probably find the building, the grounds and the huge dome of interest. One person on the tour knew nothing about astronomy, he had come only to take pictures. It was a fantastic visit, one I would happily do again. They plan to hold star parties and viewing parties in the future. They will apparently post dates on their website: https://yerkesobservatory.org/ I may try to attend one of these if I can manage it.
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