[TYPO3-english] Question to "base href"

[Santiago]

Hello,

I change the virtual host of the introduction package installation to simulate 
a rollout of the site.

Pointing the browser to the new location shows up the content without any 
styles. The sourcecode of the pages shows an entry <base href=...> to the old 
hostname, where I installed the introduction package.

I can't remember having this value set, so when was this value set, and how 
can I change it? Miss google told me, that it comes from a TS-Setting 
"config.baseURL" - but I don't know how/where to search for it.

So if anybody could shine me a light ...

kind regards

Santiago