What happens to my blogspot.com subdomain if I map a custom domain to my blog?

When you successfully map a custom domain to your Blogspot blog, your original `yourblogname.blogspot.com` subdomain does not disappear; instead, it automatically redirects all traffic to your new custom domain (e.g., `www.yourdomain.com`). This means visitors typing or clicking the old Blogspot URL will seamlessly be taken to your custom domain. This redirection helps preserve any existing links and ensures a smooth transition, allowing you to benefit from the custom domain's branding while maintaining continuity for older references.