Today I am frequently working with larger organisations and continually have to deal with people in different locations across the country or globe. This kind of context brings its own challenges and many people hope to find solutions in tooling and so did I, but hey, did I think wrong!

Before going into running multi-site events, a bit of context on team setup and the need for multi-site events.

Stage

Backlog Refinement session. 

Purpose 

Our Product Owner came up with new stories to be estimated. 14 to be precise. 
It required some preparation however.  We have 2 teams, and they do the Backlog Refinement together. 
Around 20 people in one room, partly offshore, estimating together is quite a challenge!

This article can give you some guidance on HOW to split backlog items. 
Practical tips and the "why" behind certain practices.