A newspaper article from 1881 refers to the deaths (with open verdicts of "Found Drowned" in the New River) of Katherine Fitzpatrick, a housekeeper who worked in Clarendon Road, and her daughter Kate. The bodies were found in the grates at Stoke Newington reservoir and it was suggested that they may have entered the water in "Harringay Fields". Where was this?
This 1873 map shows Harringay House and I believe its private estate/grounds/gardens were known as Harringay Park.
The newspaper article suggests that Katherine Fitzpatrick was last seen crossing the railway bridge at Hornsey - if that means Hornsey rail station then I guess Harringay Fields would be the area to the north of Harringay Park. Although I suppose its possible that the bridge in question may have been the one which is now Endymion Road, in which case Harringay Fields might refer to the area south of Harringay Park.
Thanks I've never seen the term Harringay Fields used before. It might have been a term loosely used by the journalist not familiar with the area to refer to a general location. Or, it might have been a term in local, but not official, usage and the journalist picked it up.
The article was written just as development of what is now the Ladder was beginning. This means that the old fields, the boundaries of which are shown n the 1869 OS map, could well have still been intact.
The Harringay alias Hornsey Manor map below shows something of the old field names. I know that Edward Gray leased Church Field for 21 years until his death. I think he also held Pond Field, Colliers Field and the two Beech's at some point. They may not have remained in the estate by 1880, however, as the estates that Chapman and Alexander bought did not include the full extent of Gray's holdings. (You can see the same boundaries of the fields in the manor map below Shown in the 1869 OS map).
A good proportion Farnefields (a sub manor of Harringay alias Hornsey) was also a major part of the Harringay House estate.
It could be, given the local currency of Harringay and the Harringay estate, that some or all of the fields once controlled by it were referred to as "Harringay Fields". The New River passed through the northern fields group. So the geography would work.
Just an educated guess.
As there's a Clarendon Road off Turnpike Lane (where the West Indian Cultural Centre is) I think that ties in with your thoughts that Haringey Fields would be in the area to the north of Haringey Park - between there and Turnpike Lane (which is labelled Tottenham Lane on the old map). In fact, looking at the map it appears to show 'Clarendon Cottages' (my eyesight is not good enough to be sure) in roughly the same location as where Clarendon Road is.
By 1881, the river north of Turnpike Lane was all in the grounds of the New River Company's Hornsey Reservoir to the west of the railway line. I can't that area being referred to as Harringay Fields. As far as I know there was no public access to the reservoir.