What a find! This is one of the quietest hiking areas I have been to here in Arizona. Not only is there no traffic noise, but there is little foot traffic.
When arriving to the park you are greeted by the Mediterranean style Kannally Ranch House built in the late 1920’s. It is open to the public to wander through the rooms which have the history of the building on display. The smell of old paper and the creaking of the wood plank floors will take you back in time. My suggestion is to enjoy one of the many hikes throughout the park then wander through the ranch house after. With tables in the shade, and a lovely garden on a lower level it is the perfect end to a great hike.
The hikes are under a wide open sky varying between easy and moderately easy. If you are looking for a challenge you may want to head over to Catalina State Park and do the Romero Pools Trail. What I like about these trails is the length of the trails which range from the simple 1 mile Nature Trail loop to 10 mile out and back trails. Our personal favorite is the Windmill Loop. Until we found our bearings, it took a few trips to actually get to the windmill.
On occasion, the park is open after dark for Night Skies. The night shy has a little bit of light pollution out of Tucson, but not enough to interfere with the beauty of the Milky Way. Call ahead to see when the park is open for star gazing.
The shade there is limited so be sure to wear a hat and have plenty of water if the day is hot. Oracle State Park is at 4500 feet so the temperatures are a little cooler than down in Tucson. To reach the park take Highway 77 (Oracle Road) north out of Tucson to Oracle, AZ. Follow the signs to the park entrance.
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arbitrarydustbunnies 
Great review of Oracle State Park! It sounds like the perfect place to enjoy a quiet hike and explore a bit of history. I appreciate the suggestion to check out the ranch house after the hike.