In the books
In the A Song of Ice and Fire novels, Tolos is connected by a Valyrian road to Mantarys and Bhorash. Tolos is the last inhabited city before Meereen several hundred miles to the east (Bhorash being a ruin). Travel overland between Tolos and Meeereen is dangerous, due to the proximity of the Dothraki sea to the north-east and also the harsh nature of the landscape. The Black Cliffs lie between Tolos and Bhorash.
The Tolosi are noted as being the finest slingers in the world. They use soft lead balls instead of stones, which do significantly more damage.
- Tolos at A Wiki of Ice and Fire (spoilers from the books).