King Cobra closed end of 2000, Delirium opened 2003- two full seasons in-between with empty space. Bat closed sometime in 1982, Vortex opened 1987- a bit more than four full seasons.
If I remember correctly The Bat actually stood for a couple of seasons, SBNO.
I had season passes in 1981,82,83, & 84. The Bat opened in 81, but was closed off and on that year. In 1982, they had a TV commercial saying "The Bat is back". It ran off and on that year also. In 83, it was closed for about 90% of the season. However, I was there on a few days in the summer of 83 when they had it open. On those days, it would not ever open in the morning. It was usually in the late afternoon, and you just had to pay attention if you were in the park. It was SBNO all of 84.