We visited Shikoku from 19th to 21st: stayed at Dogo Onsen hot spring in Matsuyama City on 19, while at Katsurahama beach in Kochi City on 20. Please click respective sightseeing links below for details.
Dogo Onsen:
http://www.dogo.or.jp/pc/top_eng.htm
Kochi City including Katsurahama beach: