Central Austin Properties          Ken Altes, REALTOR
The 78704 zip area encompasses the Austin neighborhoods stretching south from the Colorado River to Ben White Boulievard (Hwy 71/290).  Here are some of the neighborhoods.

The Zilker neighborhood extends south of Lady Bird Lake, approximately bounded by Lamar Boulevard to the southeast/south, La Casa Drive to the south, Rabb Road and Robert E Lee Road to the west and Barton Springs Road to the north.  Directly northwest of Zilker is Barton Hills neighborhood, which connects back to Zilker Park via the Barton Creek Greenbelt.
In 1918, Andrew Jackson Zilker deeded 35 acres surrounding Barton Springs to the City of Austin. The first homes in the Zilker area were constructed in the late 1920s.  Much of the west end of Zilker was owned by Vincent Canizzo until the late 1940s when the City of Austin, using eminent domain, forced him to sell the land on which Zilker Elementary currently sits. Shortly thereafter, the remaining land — from Ann Arbor Road to Rabb Road — was split into the Canizzo Subdivision.

The Umlauf Sculpture Garden and Flipnotics, a coffee shop and used clothing store, are popular locations for residents of South Austin. The Zilker Neighborhood is also home to many places that are familiar throughout Austin. The Tex-Mex restaurant Chuy's is very popular, and has opened many other locations all over Central Texas. Zilker Park is best known for Barton Springs; the Zilker Tree and Trail of Lights; and music festivals such as Austin City Limits and South by Southwest.
Zilker Neighborhood Association

One of Austin's oldest neighborhoods, Bouldin Creek dates to the turn of the century, with several historic homes dating to that era still standing. Most of the neighborhood's growth occurred in the 1920s and 1930s. (A 1919 street map shows Bouldin as Austin's southernmost "suburb.") Bouldin Creek was home to one of Austin's most famous voices, the late speaker, writer, and first amendment rights activist John Henry Faulk,whose boyhood residence, the landmark 1894 Victorian mansion of Dr. E.W. Herndon, is now occupied by Green Pastures Restaurant.Other neighborhood notables include Negro League baseball great Willy Wells and UT Tower gunman Charles Whitman.
Bouldin Creek Neighborhood Association  

South of the Colorado River and tucked between Interstate 35 and South Congress Avenue, sits Travis Heights, one of Austin's most sought after addresses, particularly among professionals many of whom work downtown and enjoy the quiet neighborhood just minutes from the office.  Travis Heights gets its name from the lay of the land, the streets roll up and down a series of small rises that give some residents great views of downtown while others look out on quiet woodland hollows.
The first attempts to develop Travis Heights came in the late 1880s when the area was pitched as the ideal place to build a "country mansion" away from downtown. The only way across the Colorado River in those days around Austin was by ferry. A few mansions were built, but when a stone bridge was finally completed, the developers turned to smaller homes. Real estate development in Travis Heights took off in a big way in the 1920s. 
Two parks, Big Stacy and Little Stacy, have the same rolling wooded landscape where families can play; residents can jog or cycle, and play tennis, or simply relax in some of the natural areas in the 23 acre greenbelt along Blunn Creek.
The rejuvenation of South Congress Avenue and the development of the SoCo area with its hip cafes and shops within walking distance have added even more to the popularity of Travis Heights, bounded by Lady Bird Lake on the north, Interstate 35 on the east, Congress Avenue on the west and Oltorf Street on the south. 
Another attraction of the neighborhood is its closeness to the newly rejuvenated South Congress Avenue many times called SoCo. SoCo used to be a haven for drugs and prostitution but is now full of hip cafes and stores.

South River City Citizens 
Travis Heights info
South Congress history (PDF) 
Greater South River History (PDF) 
Southwood Neighborhood Association

78704 Austin Zip Code in Central South Austin