Hi,
My website has multiple (custom) posts types. Right now they're activities, accommodations and restaurants but in the future there will be more. Every post has a custom field with the latitude/longitude. I also have a custom field with the full address.
When I'm for example on a activity page I would like to show 5 nearby accommodations and 5 nearby restaurants within 10 kilometers from the location of the activity. And vice versa.
Is this possible and if so, how should I do this? I would like to do this without a plugin if possible. Hopefully someone can get me started with this.