To build or not to build will be the question for the fate of Number 1 Waterloo Road. The landmark Victorian property lies on 0.68 of an acre, which is a rather large site for a Dublin 4 address. It borders Waterloo Lane to the rear, and the bulk of Fleming Place to the side, while occupying a corner site and first house on the prestigious Waterloo Road.

The desirability of this road is nothing new; it goes back almost 200 years, when in 1840 the Earl of Pembroke began leasing portions of his Ballsbridge estate to be developed. But all of this was on the clear understanding that these lofty piles would be constructed for “upper-class families”.

While many of these grandes dames ended up as rather rundown flats in the 1960s, number 1 has been in the same family ownership since then and has not been broken up. It has now come to the market as an estate sale through Peter Kenny of Knight Frank and is listed with an asking price of €6 million.

There are myriad options, depending on the eye of the purchaser. For its sought-after address and the size of its grounds – which are beautifully maintained to the rear – it could become a significant trophy home. With 547sq m (5,888sq ft) of floor space plus a two-bedroom period mews extending to 117sq m (1,259sq ft), it is only when you have a look at the aerial shots that the size of the grounds becomes apparent.

As it stands, the house has six bedrooms: four on the top floor and two at basement level. All four generously sized reception rooms lie on the middle level, but with the sheer size of the property it is really a moveable feast, as there are boot rooms, stores, a study and a very large laundry room at basement level. It is the largest property on Waterloo Road, with the exception of Waterloo House, a guest house which is actually two houses, Numbers 8 and 10 combined. In the area, a comparable house would be 32 Burlington Road, the former UAE ambassador’s residence, which is now owned by developer Johnny Ronan; but that site is much smaller, according to Kenny.

One of the truly great things about the house having never been in flats is that the period details all remain. The new owner will require deep pockets to bring the property – a protected structure – to modern-day living, but what a house it could be, given its period details and lovely gardens. It even has quirky remnants from the past such as a system of tubes to convey a voice message to the old kitchen at garden level, where food would then be cranked up through the dumb waiter to serve residents.

Kenny suggests that, given the address within the diplomatic belt, it could also have appeal as a residence and embassy/consulate combined; but, like all options, that will require planning.

Then there is the development potential of the site itself. “The route of least resistance could be a mews development around the property, as there is a mews on site already,” says Kenny. But a denser development has been proposed by a planning consultant engaged to examine the possibilities of this as a site in the heart of Dublin 4. The proposal would see 36 residential units comprising 22 new apartments; six apartments in the existing protected structure; six duplex units along with the renovation of the extant two-bedroom mews.

Many will keep an eye on the fate of number 1; but,whatever the outcome, as far as location and demand go, there is little on the market to match it.