Six Flags Darien Lake (SFDL) Discussion Thread in Theme Parks, Roller Coasters, & Donkeys! Posted April 5 Darien Lake released it's operating calendar for this upcoming season. You can see it here. Some highlights: - only open Friday, Saturday, and Sunday until the end of June. Friday's are only 5-9. Saturday and Sunday 11-9. - during full season Monday-Thursday is 11-7, while Friday-Sunday is 11-9.