A small islet lies off the eastern lochshore and a promontory, once an island, holds the ruins of the old castle.

Martnaham may have been part of a chain of fortalices forming a defensive line, including Drongan and Auchencloigh castles.

[3] Circa 1661 John Bonar, a schoolmaster in Ayr, wrote a poetical description of the local traditions regarding King Cole and states that[8] - "The britones marchet, tuo dayes before the feild, To Marrok's mote, for easment and for beild; Afore the night they waughter liquor fyne, Lyke filthe beasts lying like drunken swine, The castle was the caput of the old Barony of Martnaham.

An artificial causeway, which could have been cut off at pleasure, leads to the ruin, and the island itself is evidently of the same character - being made of forced earth.

The Marquis of Ailsa has a shooting and fishing lodge on the banks of the loch, which is well stocked with pike and perch, the latter having been introduced within the last thirty years."

Martnaham has had some notable rarities recorded over the years, such as smew, ring-necked duck, black tern, lesser scaup and hobby.

Shoveler, scaup, long-tailed duck and gadwall are commonly seen and glaucous, Iceland and Mediterranean gulls are occasional visitors.

[15] Martinham Wood is well established on the eastern side of the loch, featuring since at least the early 16th century with a fence or pale indicated.

[6] As an ancient woodland site Martnaham Wood has a canopy dominated by oak and birch, with abundant hazel in the understorey; sanicle, bluebell and dog’s mercury are common.

The woodland exhibits a wide diversity of fungi, mosses and liverworts, including the only Scottish record of the mushroom Mycena picta, once thought to be extinct in Great Britain.

[15] The outflow at the south-west end was in 1906 built up with stones to divert water into a lade supplying Purclewan Mill.

The Cassillis Estate has sold this now Arts & Crafts inspired manorial dwelling to Mr Dunsmuir in 1945 and it passed to his daughter and Colonel Sir Bryce Knox, his son-in-law.

A mineral railway ran close to much of the eastern side of the loch serving a colliery in Coylton.