What it is
The Hayden Flour Mill is the white concrete building with the tall silos at the north end of Mill Avenue, where the street meets Rio Salado Parkway and the lake, with Hayden Butte, the hill with the A on it, rising directly behind. It is the reason the street is called Mill Avenue and, in a real sense, the reason Tempe exists. Charles Trumbull Hayden claimed the land on the south bank of the Salt River in 1870, built a cable ferry across the river and a store beside it, and in 1874 opened a flour mill powered by canal water at the foot of the butte. The settlement that grew around the ferry and the mill was called Hayden’s Ferry before it was called Tempe.
That first mill burned, and so did its replacement; the building you see went up in 1918 and is the oldest cast-in-place concrete structure in the city. The silos came later. Flour was ground here for 124 years, until 1998, when the last operator shut it down and the mill went dark at the end of a Mill Avenue that was just coming back to life. The city of Tempe bought it in 2003. Since then it has been a landmark, a festival backdrop and the subject of three redevelopment plans, the first two of which collapsed before construction.
Why leave Scottsdale for it
Not on its own; for ten minutes at the start of a Tempe morning. The mill is the origin story of the East Valley in one building, visible from the sidewalk, with the butte trail beside it and the lake in front, and seeing it explains Mill Avenue, the canals in our Hohokam canals note and the agricultural Valley that Scottsdale was also part of. Our museums and attractions note has it as the free, outdoor history stop in Tempe.
The practical version
Eighteen minutes from Old Town: Scottsdale Road south into Rural, west on University, north on Mill to the end. Downtown garages. The grounds are fenced and the building is closed; the view is from the sidewalk, the butte trail and the lake path. The redevelopment approved in 2023 had not opened as of our October 2026 check, and the state of the site changes; read the news before you promise anyone a restaurant in a flour mill.
When to go
Early morning, any month, when the light is on the east face of the mill and the butte trail is cool; the climb to the A takes twenty minutes and gives the one view that puts the mill, the lake, the campus and the Mill Avenue bridges in a single frame. Evening from the lake path on the north shore is the other good look, the mill lit against the butte. December brings the Tempe Festival of the Arts along Mill, which has used the mill’s plaza as a stage and a backdrop. Summer is for the first hour after sunrise and nothing else; the butte has no shade.
What to do
Read the markers at the corner, which cover Hayden, the ferry and the fires. Walk the perimeter along Mill and Rio Salado for the silos and the loading dock. Take the Hayden Butte trail, whose lower trailhead is beside the mill and which the redevelopment plan promises to improve. Then walk south down Mill, which is the whole reason the street exists, past the bars and the 1890s storefronts to the campus. For the full story, drive ten minutes south to the Tempe History Museum, whose permanent galleries put the mill, the canals and the Hayden family in context.
With kids
The butte climb is the thing: short, steep, a real summit with an A to touch and a view of the whole town. The mill itself is a two-minute look for a child. Tempe Beach Park and its playground are across Rio Salado.
The neighborhood
The mill anchors the north end of downtown Tempe, between Mill Avenue’s restaurant blocks and the lake. The Omni Tempe, the new hotel at University and Mill, is a ten-minute walk south; the Tempe Center for the Arts is across the Mill Avenue bridges to the west.
The story
Charles Trumbull Hayden was a Connecticut-born freight merchant who, in 1870, claimed two sections on the south bank of the Salt River where a butte came down to the water and the river could be crossed. He built the ferry, the store and, by 1874, a flour mill fed by a canal dug along the line of the Hohokam ditches that had watered the same ground a thousand years earlier. The road the farmers used to haul wheat to the mill became Mill Avenue; the settlement was Hayden’s Ferry until a visitor compared the butte and river to the Vale of Tempe in Greece. Hayden’s son Carl, born in the adobe across the street, served Arizona in Congress for 56 years.
The mills burned, twice, and the 1918 rebuild in poured concrete was meant to be the one that did not. It outlasted the family, the national millers, the end of Valley wheat farming and the mid-century collapse of Mill Avenue, and ground flour until 1998. Tempe bought it in 2003 and signed two development agreements in the years that followed; neither built anything, the second undone by the recession.
The third attempt is the current one. In October 2023 the council approved a 60-year lease with Sunbelt Holdings and Venue Projects: restore the mill and silos, add about six low buildings on roughly five acres for restaurants and shops, build a public park and a proper butte trailhead, and design it with the Salt River Pima-Maricopa Indian Community, the preservation office and former mill workers at the table. The city keeps the land and takes three percent of net revenue. Groundbreaking was projected for 2025. When we checked in October 2026 the site was still fenced and no construction start or opening date had been published. The mill has waited before.
The Scottsdale connection
Scottsdale was wheat and alfalfa country too, watered by the Arizona Canal from 1885, and its early farmers hauled grain to the Valley’s mills, Hayden’s among them. The canal system that fed the mill is the one the Salt River Project runs today past Scottsdale’s golf courses, and Carl Hayden’s half-century in Washington built the dams that made modern Scottsdale possible.
Getting there
Scottsdale Road south from Old Town; it becomes Rural Road at the Tempe line. West on University Drive, north on Mill Avenue to its end at Rio Salado Parkway; the mill is on the right, under the butte. About eighteen minutes with no traffic. Park in the downtown garages, or take the Valley Metro streetcar along Mill, which stops a block away. Our getting around note has the rideshare math.