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Radio continuum, microwave and gamma-ray images of the Milky Way reveal aconspicuous, loop-like structure that fills almost half of the northernGalactic hemisphere, called Loop I. The interior of Loop I is shining in softX-rays, and its eastern base is a bright, elongated structure dubbed the NorthPolar Spur (NPS). After 40 years of debates, two contradictory views of LoopI/NPS are still defended: on the one hand, the NPS is a volume of expanding hotgas that envelops and extends the northern Fermi Bubble (FB) known to be blownby the Galactic center, and Loop I marks the shock front; on the other hand,the NPS is a nearby cavity of hot gas blown by supernovae, Loop I is its shockfront and they are coincidentally located in the direction of the FB. To anobserver at the Sun, both structures can produce the same perspective view,although the former has a size comparable to the Milky Way itself, and thelatter a diameter of a few hundreds parsecs. The energy involved varies by3-4~orders of magnitude, and the solution has various important consequences. Idiscuss recent results which have a connection with Loop I/NPS, overlooked orused as arguments in the two opposite ways. They involve very differentspacecraft, from a 12 Kg Cubesat (HaloSat) to major space-borne observatories(HST, Gaia, and Spektr-RG). I make use of 3D~maps of dust and a massive starcatalog. Considering all constraints, it is clear that there is no entirelylocal or entirely distant scenario that is free from contradictions with someof the data analyses or from improbable coincidences. I discuss a speculativescenario, partially inspired by recent BF and Milky Way gas models, combiningnear and far aspects and seeming to be able to meet the various constraints.However, new data and models are needed to bring the controversy to a close andwe can still expect new episodes of this long story.

North Polar Spur/Loop I: gigantic outskirt of the Northern Fermi bubble or nearby hot gas cavity blown by supernovae?