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Bucharest, Romania · sunsets and sunrises down its streets

The evenings the sun sits on Ceaușescu's palace

In Bucharest, Romania's capital, Union Boulevard (Bulevardul Unirii) was laid out from 1984, under the communist leader Nicolae Ceaușescu, as the axis of a new civic centre that ends at his giant Palace of the Parliament. Seen from the boulevard's other end, Alba Iulia Square, the setting sun comes down exactly onto the top of the Palace on a few evenings in late March and mid-September. 480 Bucharest streets have such evenings, each on its own days. Change the day and watch the sun slide across the rooftops until it reaches the end of the street.

Find your street See the map

Find your street See the map

In Bucharest, Romania's capital, Union Boulevard (Bulevardul Unirii) was laid out from 1984, under the communist leader Nicolae Ceaușescu, as the axis of a new civic centre that ends at his giant Palace of the Parliament. Seen from the boulevard's other end, Alba Iulia Square, the setting sun comes down exactly onto the top of the Palace on a few evenings in late March and mid-September. 480 Bucharest streets have such evenings, each on its own days. Change the day and watch the sun slide across the rooftops until it reaches the end of the street.

On Union Boulevard, seen from Alba Iulia Square, the lower edge of the sun rests on top of the Palace around 29 March 2027 (at 19:25) and again around 13 September 2027 (at 19:17). The sun sets onto the Palace on every evening of the window, 25–31 March and 11–18 September: onto its highest block on 28–31 March and 12–14 September, and onto its lower parts on the other evenings. The closer you walk to Unirii Square, the higher the Palace stands in the sky and the more the date moves. From Unirii Square itself, the sun reaches its top only around 6 April, and in autumn earlier, on 5 September.

September is the better bet: in mid-September about half the evenings had a nearly clear sky at sunset over the last 25 years, against fewer than 4 in 10 in late March.

Which streets catch the sunset on the chosen evening

Each lit line is a straight stretch of street with the sun at its end on the chosen day. There is no evening without one: on every day from 1 October 2026 to 30 September 2027, between 24 and 67 stretches of Bucharest street line up with the sunset.

The longest

    All the lit lines run almost parallel to the arrow in the corner, the direction of sunset (or sunrise) on the chosen day. Tap a line to see the street.

    Why it happens twice a year

    The sun does not set in the same place every evening. At the winter solstice, on 21 December, Bucharest sees it set to the south-west, at 237° (measured clockwise from north). At the summer solstice, on 21 June, it sets to the north-west, at 305°. Between the two, the setting point slides along the horizon by up to 0.55° a day, around the equinoxes, and nearly stands still near the solstices.

    230°250°270°290°310°JanFebMarAprMayJunJulAugSepOctNovDecUnion Blvd, 273.5°29 Mar13 Sep
    The direction in which the sun comes down onto the buildings at the end of Union Boulevard, seen from Alba Iulia Square, day by day through 2027. The gold line is the boulevard's axis: the sun crosses it in spring and crosses back in autumn.

    A street pointing anywhere between those two ends is caught twice: once in spring, as the setting point moves north, and once in late summer or autumn, as it moves back. Union Boulevard, begun in 1984 as the axis of the civic centre built under Nicolae Ceaușescu, which ends at the Palace, points at 273.5°, almost due west, so its evenings fall close to the equinoxes. A street pointing at 305° would have both of them pressed against 21 June.

    Streets pointing outside that fan never have the sun at their end. Decebal Boulevard, looked along from Piața Muncii toward Alba Iulia Square, points at 230°, further south than the sun sets even on 21 December.

    In New York the event has a name: Manhattanhenge, made famous by the astrophysicist Neil deGrasse Tyson, director of the Hayden Planetarium, for the evenings in late May and mid-July when the sun sets at the end of Manhattan's cross streets, over the open horizon across the Hudson. In Bucharest the end of the street is usually closed by buildings, so the sun comes down onto them rather than onto the horizon. Bucharest has no grid like Manhattan's, but it has its boulevards, each with its own evenings.

    How many evenings are clear

    The alignment is only half the luck. The chart shows, for each week of the year, the share of evenings in 2001–2025 with a nearly clear sky at sunset (30% cloud cover or less, from the ERA5 reanalysis, in the grid cell covering north-west Bucharest). August is the clearest month, with almost 6 evenings in 10; July to October are better than the rest of the year, and November to January and May are the cloudiest, with about 3 clear evenings in 10 (one in four in the worst weeks, around early December).

    0%20%40%60%31%32%28%26%34%31%33%29%33%32%35%39%39%40%35%33%42%34%32%28%31%28%33%32%42%43%49%51%53%50%52%59%59%57%56%49%49%39%37%43%37%42%45%38%33%28%27%26%22%27%32%37%JanFebMarAprMayJunJulAugSepOctNovDec
    Share of clear evenings at sunset, by week, Bucharest, 2001–2025

    How it was worked out

    The streets come from OpenStreetMap: 16,214 named street segments within Bucharest's city limits. The page looks for stretches where the street's centre line strays no more than 3 metres from a straight line for at least 300 metres, and merges the two carriageways of each boulevard into one axis. That leaves 723 stretches on 579 streets that run roughly east–west with their far end in view; 662 of them, on 533 streets, have the sun at their end at least once in the coming year.

    On each stretch the observer stands at one end, eyes 1.6 metres above the ground, and looks along the axis. What closes the view is whatever rises highest above eye level along the axis, from the last 15% of the stretch out to 12 kilometres: a building or, where none stands higher, the ground. The buildings are 138,177 from OpenStreetMap, plus 5,135 separately mapped building parts such as the Palace's central block; the height is recorded on the map for about 6% of the buildings, worked out from the number of floors at 3 metres a floor for about 15%, and estimated from the building's type and size for about 80%. The ground comes from the Copernicus GLO-30 elevation model, filtered to strip roofs and tree crowns narrower than about 150 metres; under the Palace it is set to 87.5 metres, the platform level on the 1991–1993 cadastral plans.

    The aligned evening is the one when the sun, with its lower edge resting on that skyline of buildings, stands on the street's axis. For every direction 0.05° apart either side of the axis, out to the gap between the façades at the far end, the page finds what rises highest on that line of sight; the directions where that is the far end, not a side façade, make up the profile the sun can set onto. It then follows the sun's slanting path down: a day is aligned when the sun's lower edge comes down onto that profile, so it sets at the very end of the street rather than behind a block along its side. The window is the run of such days. The far building's height moves the dates: a 40% error in an estimated height moves the best day by 0.9 days in the median case (by at most 2.6 days in 9 cases out of 10), and a 10% error in a recorded height by 0.4 days. Close to the solstices, where the setting point barely moves, the same error can move the date by weeks. The sun's position comes from the NOAA equations, with refraction for ordinary air; it differs from NASA's ephemerides by less than a hundredth of a degree.

    Trees, poles, wires, billboards, buildings missing from OpenStreetMap and buildings more than about a kilometre beyond Bucharest's city limits are not in the calculation; on streets looking out of the city, the real skyline may be a little higher. Times are rounded to the minute. On Union Boulevard, for example, the trees along the sides and the fountain jets can hide part of the view, and haze near the horizon often swallows the sun before it reaches the buildings. The view at the top of the page is drawn from the same data; the glow on the asphalt is a drawing effect.

    More on the site

    Sources

    1. Streets, buildings, heights, squares: OpenStreetMap contributors (ODbL), Overpass API, 28 September and 1 October 2026 openstreetmap.org/copyright
    2. Terrain: Copernicus GLO-30 DEM, ESA (© DLR e.V. 2010–2014 and © Airbus Defence and Space GmbH 2014–2018, provided under Copernicus) dataspace.copernicus.eu/explore-data/data-coll…
    3. The Palace's platform, 86–89 m: spot heights on the 1:500 sheets 15E2–15E4 (1991–1993) and the 1:2000 sheet 15-16GF around the Palace, read for the page on Uranus Hill mariuscomper.uk/dealul-uranus/en/
    4. Height of the Palace, 84 m above its zero level (cota 0): International Conference Centre, Palace of the Parliament cic.cdep.ro/en/prezentare/cladire
    5. Sun position: NOAA equations (after Jean Meeus, Astronomical Algorithms), checked against NASA JPL Horizons ephemerides gml.noaa.gov/grad/solcalc/calcdetails.html
    6. Atmospheric refraction: G. G. Bennett, 'The Calculation of Astronomical Refraction in Marine Navigation', Journal of Navigation 35 (1982) doi.org/10.1017/S0373463300022037
    7. Cloud at sunset and sunrise, 2001–2025: ERA5 reanalysis (ECMWF, Copernicus Climate Change Service), grid cell centred at 44.5° N, 26.0° E, via Open-Meteo open-meteo.com/en/docs/historical-weather-api
    8. Manhattanhenge: Neil deGrasse Tyson, Hayden Planetarium, American Museum of Natural History amnh.org/research/hayden-planetarium/manhattan…
    9. Union Boulevard and the Civic Centre: works began on 25 June 1984 (Adevărul, 25 June 2023) adevarul.ro/istoria-zilei/25-iunie-ziua-in-car…
    10. D. Light and C. Young, 'Urban space, political identity and the unwanted legacies of state socialism: Bucharest's problematic Centru Civic in the post-socialist era', Nationalities Papers 41 (2013) eprints.bournemouth.ac.uk/21511/