I have been to this spa on several occasions, In fact, I have been there over Mothers Day weekend which is quite possibly the busiest day of the year. Even then, you are able to find wonderful places to relax.
Do not go to Glen Ivy expecting the prissy, secluded spa environment at some private expensive day spa where you feel like they are watching your every move, because Glen Ivy Hot Springs is a place where you have the freedom to make your own experience. Some areas are busier than others and they do allow kids so some areas may not be as "relaxing" but I we always able to find a place to relax without issue.
You need to bring your own supplies (robe, coverup, sandals, etc) but they have all the items to take a shower. Personally I prefer to be in my own stuff anyway. Definitely bring an old swim suit because the mud bath is amazing for your skin (especially dry elbows) but it will stain light colored suits. I usually just wear an old one to the spa, its not like I am there to impress anyone anyway.
The thing I like about Glen Ivy is I never feel intimidated like I have at other spas, its really is an every-mans day spa. They have services to make any budget happy and honestly I couldn't think of a more relaxing place in So Cal for the money.
Pros: Lots of choices for Relaxing
Cons: It can get very busy
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