Heorot is the stronghold of king Hrothgar in the epic poem Beowulf.
Heorot is Old English for hart or stag; see under Hartlip at BBC page.
The Heorot series by Steven Barnes, Jerry Pournelle and Larry Niven is named after the stronghold. It contains the following books:
Larry Niven's Destiny's Road is also set in the same universe, but only mentions the events in Legacy Of Heorot in passing.