There are microwave links across Europe: https://sniperinmahwah.wordpress.com/2016/01/26/hft-in-the-banana-land/ https://sniperinmahwah.wordpress.com/2016/01/2

There are microwave links across Europe: https://sniperinmahwah.wordpress.com/2016/01/26/hft-in-the-banana-land/ https://sniperinmahwah.wordpress.com/2016/01/26/hft-in-the-b... There are apparently shortwave links across the Atlantic: https://sniperinmahwah.wordpress.com/2018/05/07/shortwave-trading-part-i-the-west-chicago-tower-mystery/ https://sniperinmahwah.wordpress.com/2018/05/07/shortwave-tr... https://sniperinmahwah.wordpress.com/2018/07/16/shortwave-trading-part-iv-sleuthing-examples-research-tools-techniques-deputies-wanted/ https://sniperinmahwah.wordpress.com/2018/07/16/shortwave-tr... These should have a lower latency than fibre links although the shortwave link will probably have rather a low data rate.