134, Dundas is associated with its long time tenant Mara's textiles store. The building was erected in the Art Deco architectural style, and its storefront was patterned with a diamond design that copies the raised design around the perimeter of the façade still visible today. Reflecting the highly fashionable and artistic use of art glass in storefronts built in the late 1880s and 1890s, Mara's had one of the finest art glass storefronts in the downtown. As was typical at the turn of the twentieth century, the intricate colourful designs of the upper part of the storefront contrasted with the unbroken expanse of plate glass below through which goods could be seen on display. The use of art glass remained a prominent feature of commercial architecture well into the 1920s.

Initially Mara's was called the T.E. Mara Company Limited with stores at 153 and 155 Dundas, as well as a stall at the market. Mara's established itself at 134, Dundas towards the end of the nineteenth century and became W.L. Mara's Dry Goods. Thomas Mara, like other famous dry goods dealers of the time, including Timothy Eaton and T.F. Kingsmills, made frequent trips to England and continental Europe to purchase wholesale woolens, table linens and other textiles for the store. These dry good dealers would often purchase directly from suppliers' factories or mills. Mara's, like Kingsmill's and Eaton's, created business through wide advertising, what today would be called aggressive publicity campaigns, in the local press. It was also one of the first stores to offer sales on credit, which started the new practice whereby customers could buy now and pay later through installments.

More recently, 134, Dundas is associated with another long-time tenant that is, by now, a fixture of the downtown. This is "To Wheels" which is popular among cyclists and reflects a long-time historically-significant hobby of many Londoners.