Every event (website) is assigned a unique URL. All URL’s are built up as follows: https://uniquecode123abc.momice.com.
The ‘https’ refers to the encryption of all (registration) data that passes through the website.
The unique code at the end of the URL makes it impossible for people to find the website without the link in the invitation.
.momice.events is the head domain of all Momice events.
If you prefer to use a custom URL, than read more about 'masking'.