For some reason, Fundamentalists -- and not a few other Protestants -- think the best argument against the institution of the papacy is the argument that Peter never was in Rome. The problem for them is that he really was there, as most Protestant scholars affirm. Still, for the recalcitrant, here's proof.
Clement of Rome
"But, to leave the examples of antiquity, let us come to the athletes who are closest to our own time. Consider the noble examples of our own generation. Through jealousy and envy, the greatest and most righteous pillars were persecuted, and they persevered even to death. Let us set before our eyes the good apostles: Peter, who through unwarranted jealousy suffered not one or two but many toils, and having thus given testimony went to the place of glory that was his due" (Epistle to the Corinthians, 5:1 [ca. A.D. 80 or 96]).
"Not as Peter and Paul did, do I command you. They were apostles, and I am a convict" (Epistle to the Romans, 4:3 [A.D. 110]).
"Since it would be too long to enumerate in such a volume as this the successions of all the [local] churches, we shall confound all those who, in whatever manner, whether through self-satisfaction or vainglory, or through blindness and wicked opinion, assemble other than where it is proper, by pointing out here the successions of the bishops of the greatest and most ancient church known to all, founded and organized at Rome by the two most glorious apostles, Peter and Paul, that church which has the tradition and the faith which comes down to us after having been announced to men by the apostles" (Against Heresies, 3, 3:2 [A.D. 180]).
"Matthew also issued among the Hebrews a written Gospel in their own language, while Peter and Paul were evangelizing in Rome and laying the foundation of the Church" (Against Heresies, 3, 1:1 [A.D. 180]).
"It is recorded that Paul was beheaded in Rome itself, and Peter, likewise, was crucified, during the reign [of the Emperor Nero]. The account is confirmed by the names of Peter and Paul over the cemeteries there, which remain to the present time. And it is confirmed also by a stalwart man of the Church, Gaius by name, who lived in the time of Zephyrinus, Bishop of Rome. This Gaius, in a written disputation with Proclus, the leader of the sect of Cata-phrygians, says this of the places in which the remains of the aforementioned apostles were deposited: 'I can point out the trophies of the apostles. For if you are willing to go to the Vatican or to the Ostian Way, you will find the trophies of those who founded this Church'" (Disputation with Proclus [A.D. 198] in a fragment from Eusebius, History of the Church, 2, 25:5).
Dionysius of Corinth
"You have also, by your very admonition, brought together the planting that was made by Peter and Paul at Rome and at Corinth; for both of them alike planted in our Corinth and taught us; and both alike, teaching similarly in Italy, suffered martyrdom at the same time" (Epistle to Soter of Rome [A.D. 166] in a fragment from Eusebius, History of the Church, 2, 25:8).
"Let us see what milk the Corinthians drained from Paul; against what standard the Galatians were measured for correction; what the Philippians, Thessalonians, and Ephesians read; what even the nearby Romans sound forth, to whom both Peter and Paul bequeathed the gospel and even sealed it with their blood" (Against Marcion, 4, 5:1 [A.D. 207]).
Clement of Alexandria
"The circumstances which occasioned . . . [the writing] of Mark were these: When Peter preached the Word publicly at Rome and declared the gospel by the Spirit, many who were present requested that Mark, who had been a long time his follower and who remembered his sayings, should write down what had been proclaimed" (Sketches [A.D. 190], in a fragment from Eusebius, History of the Church, 6, 14:1).
Peter of Alexandria
"Peter, the first chosen of the apostles, having been apprehended often and thrown into prison and treated with ignominy, at last was crucified in Rome" (Penance, Canon 9 [A.D. 306]).
"When Nero was already reigning Peter came to Rome, where, in virtue of the performance of certain miracles which he worked . . . he converted many to righteousness and established a firm and steadfast temple to God. When this fact was reported to Nero . . . he sprang to the task of tearing down the heavenly temple and of destroying righteousness. It was he that first persecuted the servants of God. Peter he fixed to a cross, and Paul he slew" (The Deaths of the Persecutors, 2, 5 [A.D. 316]).
Cyril of Jerusalem
"While the error [of Simon Magus] was extending itself, Peter and Paul arrived [in the city of Rome], a noble pair and the rulers of the Church, and they set the error aright" (Catechetical Lectures, 6, 14 [A.D. 350]).
"In addition to this, there is also the companionship of the vessel of election, the most blessed apostle Paul, who contended and was crowned with a glorious death along with Peter in the city of Rome in the time of Caesar Nero . . . . They equally consecrated the above-mentioned holy Roman Church to Christ the Lord; and by their own presence and by their venerable triumph they set it at the forefront over the others of all the cities of the whole world. The first see, therefore, is that of Peter the apostle, that of the Roman Church, which has neither stain nor blemish nor anything like it" (Decree of Damasus, 2 [A.D. 382]).
"At Rome the first Apostles and bishops were Peter and Paul, then Linus, then Cletus, then Clement, the contemporary of Peter and Paul" (Panacea Against All Heresies, 27, 6 [A.D. 374]).
"You cannot deny that you are aware that in the city of Rome the episcopal chair was given first to Peter; the chair in which Peter sat, the same who was head--that is why he is also called Cephas--of all the apostles; the one chair in which unity is maintained by all" (The Schism of the Donatists, 2:2 [A.D. 367]).