Blackheath Enclosure

Blackheath sits on the site of an Iron Age enclosure. 
the Iron Age was from about 500 BC to when the Roamn's arrived. 
View on Google maps.

Is an Iron Age Roundhouse what would have sat inside the enclosure?  Or would it have been more defensive?

Below is some information off the web. 
If any copyright is infringed by my posting this here it will be removed if I am made aware of it.

A SURVEY OF DEFENDED ENCLOSURES IN PEMBROKESHIRE 2006-07
http://www.cambria.org.uk/projects/prehistdefenc/pemsn10sn11sn12.pdf
Prepared by Cambria Archaeology for Cadw
REPORT NO. 2007/01 PROJECT RECORD NO. 54269
March 2007
3805 LLANTEG ENCLOSURE
PRN 3805 NGR SN17421001
SITE NAME LLANTEG ENCLOSURE
SITE TYPE DEFENDED ENCLOSURE FORM Documents

PERIOD Iron Age CONDITION E

DESCRIPTION
Llanteg Enclosure has been virtually destroyed. It was formerly defined by a hedge-bank with a low shallow ditch to the northeast and southwest sides. A turnpike road was driven through the enclosure in the early 19th century and a small farmhouse with outbuildings had been built in the centre of the enclosure by at least the end of the 19th century. The house has been extended and gardens and a yard created to the west and north of it. Road widening and straightening in 1984 effectively removed what remained on the enclosure on to the south. This work exposed the clay-loam bank, which had a possible burnt layer towards its base. All that remains of the enclosure is a hedge-bank defining its northeast side - presumably on the defensive bank - and possible a small portion of the interior just within this bank.
The site lies on level ground at c. 145m above sea level.
K Murphy 3 November 2006

LLANTEG ENCLOSURE
Iron Age DEFENDED ENCLOSURE
SN1742010010 Llanteg
Substantial
Destruction
Condition: Accessibility: Visible from road/path
Visitor Potential: Low Interpretation Potential: High

This Iron Age enclosure has been almost completely destroyed as a result of 19th and 20th century road-building. During the 1830s, the turnpike road was built through the centre of the enclosure. Subsequently, Blackheath farmhouse and outbuildings were built on the site. In 1984, road improvements saw further damage inflicted, which means that now hardly any vestiges of the monument remain. It is one of a series of similar Iron Age enclosures which dot the south Pembrokeshire landscape.
NPRN: 0 PRN: 3805
Listed Building Number: Scheduled Ancient Monument Number:
Ownership: Private
Management: Private