First of all, I am sorry to post this issue here but I can’t find where to report this twitter network issue, I have contacted twitter support but they only offer support regarding twitter accounts. This issue is related with the twitter network.
I am from Spain, when I query twitter.com using my ISP’s DNS server I get this response:
NSLOOKUP> twitter.com 18.104.22.168 Respuesta no autoritativa: Nombre: twitter.com Addresses: 22.214.171.124 126.96.36.199
This IP’s are fine, they are in Europe and they have 42ms of ping.
The problem is when I use Google-Public-DNS twitter gives me IP’s from United States when I query for twitter.com.
NSLOOKUP> twitter.com 188.8.131.52 Respuesta no autoritativa: Nombre: twitter.com Addresses: 184.108.40.206 220.127.116.11 18.104.22.168 22.214.171.124
This IP’s are 130ms away from my location.
I have reported this issue to Google-Public-DNS support (Issue 1381) and they say that is a problem in Twitter DNS infrastructure.
When I use Google DNS (126.96.36.199) to resolve twitter.com Google ask to TwitterDNS from this IP (188.8.131.52/24) but for some reason TwitterDNS thinks that the IP 184.108.40.206/24 is located in United States, but it is located in netherlands (EUROPE) so it gives GoogleDNS a IP in the United States and then GoogleDNS gives that IP to me.
This issue happens to all ISP’s in SPAIN, so it affects to every single Twitter user in Spain that uses Google DNS (220.127.116.11).
Given that you are being routed (correctly) through Brussels, and Twitter is incorrectly geo-locating IPs on Telefonica as well, I would suggest that you contact Twitter support (https://support.twitter.com/forms) and suggest that they use a more accurate IP geo-location database.