There are few places accessible to RV's along the SP public access beaches. When you do find a spot to drive onto the beach sand, be prepared for the constant wind-blown sand. It will coat everything, and because it contains salt, it will quickly rust everything it contacts.
We stayed most of a week, and will never stay on the island again. Port Isabel has several RV parks that are more wind-protected and much cheaper rates.
RVing in the Rio Grande Valley lists almost every RV park there.
Another South Texas RV park website. Hope it helps.
We stayed one month in Los Fresnos, TX; about 15 miles from the island bridge. Los Fresnos has a very good rodeo during the winter months too. While you are in the Rio Grande Valley be sure to attend the only
legal bull fight in the U.S.A. It is an experience your family will never forget.
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2000 Winnebago Ultimate Freedom USQ40JD
, ISC 8.3 Cummins 350, Spartan MM Chassis. USA IN 1SG 11B5MX,Infantry retired;Good Sam Life member,FMCA.
" My fellow Americans, ask not what your country can do for you, ask what you can do for your country. John F. Kennedy