I've written about this on the blog before, but the forthcoming "Tenkar's Landing" crowdsourced project has got me thinking about it again - how big does your sandbox need to be?
What I like about the island that Tenkar's Landing rests upon is that it is limited in scope - about 65 miles long and 15 miles wide on average. Assuming 6 miles from center to center of each hex it puts the total land mass at just under 1000 square miles. That's a lot of exploring.
Can the party leave the island? Sure. Tenkar's Landing is a trading port after all. I do have much of the surrounding area mapped too (but have few if any plans to detail just yet). Hopefully the players and their characters will find enough excitement on the island to occupy themselves for a good long time.
Crowdsourcing the sandbox of Tenkar's Landing should be an interesting experiment. An island with the ruins of an extinct advanced civilization colonized by a now failing empire to be detailed by a dozen or two creative types from the OSR community. I may want to be a player in the resulting sandbox...
So, how large a sandbox do you like for your campaigns and why?
* note - this will be a crowdsourced project, not a crowdfunded project. By the community, for the community.