I have this too and i'd like to know what it is! Its like a roundish protrusion of flesh with a hole in the end but not big enough to put a finger through. I've looked at diagrams and not seen anything like this :[

It sounds like the hymen, although the hymen is at the entrance of the vaginal opening.

At different times of your cycle your cervix can be low in your vagina. You can however not stick your finger into your cervix.

i have that too and my boyfriend just found it and i never noticed it before. ya its like a ring is what he said. my finger fits through it and it is a hole about a half inch deep. i wanna no what it is too. but i think it is just something ur born with. i just cant believe i never noticed it. is it normal??

my friend told me about that ... but you have to open that and that is the opening into your vagina weirdly enough and it either opens up naturally or you have to open it when you stick your tampon in thats why it hurts so much because your are like opening your vagina

The 'ring' is your hymen. Some time during your puberty the hymen will pull back, thicken and become elastic because of your feminine hormones. This can happen in the beginning of puberty, at the end or anywhere in between. Before that happens the hymen can be thin, veiny and tight and it can cover some part of the vaginal entrance.

Your hymen can tear from physical exercise like horse back riding, gymnastics, jumping, cycling, skiing, dancing, martial arts, water slides, water skiing or cheer leading. Your hymen will tear and wear away from masturbation, intercourse, tampon use and child birth. Some times a doctor might have to help it along by cutting it. This is a very small procedure that can be done with local anesthetic. This is however not normally needed.

Susan is absolutely correct. It is your hymen.