Access multiple websites from one domain?

Hello,

I am new to Nginx. Got to know about it when installing GitLab. I have gone through some of the configuration files and have also read the documentation here: http://nginx.org/en/docs/beginners_guide.html

However I cannot really find the answer I am looking for.

I am using nginx configuration file that comes with GitLab. Can be found here:
https://github.com/gitlabhq/gitlabhq/blob/master/lib/support/nginx/gitlab

My problem is that I can access the website (Gitlab) as follows: http://localhost

However I would like to access the website as follows: http://localhost/gitlab

Is there a way how I can do this by changing gitlan nginx configuration file?

I have only one domain and I would like to use it as follows if possible:

http://domain/gitlab
http://domain/webapp2
http://domain/webapp3
etc...