Round Mountain is a small, unincorporated community located in Blanco County, Texas. The area experiences a subtropical climate, characterized by hot summers and mild winters. Summers are often hot and humid, with temperatures averaging in the 90-100°F range, while winters are generally mild, with temperatures seldom dropping below freezing. Spring and fall seasons are pleasant, offering comfortable temperatures and occasional rainfall.

The hydrology of Round Mountain is primarily influenced by the Pedernales River, which flows through the region. The river provides ample opportunities for water-based activities such as fishing, swimming, and boating. Additionally, several creeks and springs dot the landscape, further adding to the hydrological richness of the area.

Outdoor enthusiasts will find a variety of recreational opportunities in Round Mountain. The Pedernales Falls State Park, located nearby, is a popular destination for hiking, camping, and birdwatching. The park is known for its stunning limestone cliffs, scenic trails, and the picturesque Pedernales Falls, where visitors can swim and relax. Additionally, the area offers opportunities for hunting, horseback riding, and exploring the beautiful Texas Hill Country landscape.