I researched in some place.
paracas square library743.43Kbps (92.37KB/sec)
British Library ( registered user )2.24Mbps (280.38KB/sec)
You can become registered user easily.
You need only few steps on online.
barbican center ground floor4.08Mbps (510.56KB/sec)
ConclusionIn the point of wi-fi speed, barbican is the best place.
But I think British Library is the best.
Because there are a lot of desk and chair and they are more ergonomic than barbican's ones.
In addition, British Library is more silent than barbican.
So, I came to British Library and wrote this article.
EF School(an addition)
This is the school which I study English.