1. Oregon became a state on June 25, 1859. On this day, President James Buchanan signed the bill admitting Oregon as the 33rd state in the Union. The newly-formed state had a population of 52,465 at the time.

2. The first officially recorded baseball game in Oregon was played on June 25, 1866. The game was between the Pioneer and Occidental clubs, and was played on the grounds of the Portland Cricket Club.

3. On June 25, 1918, the Oregon Gas & Electric Company began operating the Pelton Round Butte Hydroelectric Project. The project harnessed the power of the Deschutes River to generate electricity, and it remains operational to this day.

4. The Oregon Zoo opened its doors on June 25, 1959. Originally known as the Portland Zoo, it was established on the site of the former Washington Park Zoo. Today, the Oregon Zoo is home to over 2,000 animals from around the world.

5. June 25, 1977 marked the opening of the Oregon Vortex, a roadside attraction located in Gold Hill. The site is known for its strange optical illusions and gravitational anomalies, and has been a popular tourist destination for over four decades.