San Marcos, Texas, located in Hays County, offers a beautiful blend of natural attractions and outdoor recreation opportunities. The city experiences a humid subtropical climate, characterized by hot summers and mild winters. Average high temperatures range from the 90s°F (32-37°C) in summer to the 60s°F (15-20°C) in winter. Rainfall is fairly evenly distributed throughout the year, with occasional heavy showers and thunderstorms. The San Marcos River, a prominent hydrological feature, runs through the heart of the city, providing a picturesque setting for various water-based activities such as swimming, tubing, and canoeing.

The San Marcos River is home to various hydrology constituents, including numerous species of fish, turtles, and other aquatic wildlife. It also houses the famous endangered Texas blind salamander, which draws researchers and nature enthusiasts alike. The river's clear water and lush surroundings make it a popular spot for snorkeling and scuba diving.

For outdoor enthusiasts, San Marcos offers an abundance of recreational opportunities. The city boasts several parks and nature preserves, such as the Spring Lake Preserve and the Purgatory Creek Natural Area, where visitors can enjoy hiking, biking, and bird-watching. A short drive from the city takes you to the stunning natural wonders of the Hill Country, including the iconic Canyon Lake and the vast Balcones Canyonlands National Wildlife Refuge, offering additional opportunities for exploration and outdoor adventure. Whether you're seeking to enjoy the river, hike through scenic landscapes, or simply take in the natural beauty of the area, San Marcos offers a diverse range of outdoor activities for nature lovers of all kinds.